{"id":25588,"date":"2025-10-31T13:47:48","date_gmt":"2025-10-31T08:17:48","guid":{"rendered":"https:\/\/onlinefreenotes.com\/?p=25588"},"modified":"2025-12-12T06:55:20","modified_gmt":"2025-12-12T06:55:20","slug":"study-of-compounds-nitric-acid-icse-class-10","status":"publish","type":"post","link":"https:\/\/mockupbw.site\/2025\/onlinefreenotes\/study-of-compounds-nitric-acid-icse-class-10\/","title":{"rendered":"Study of Compounds-Nitric Acid: ICSE Class 10 Chemistry"},"content":{"rendered":"\n<p>Get notes, summary, questions and answers, MCQs, extras, competency-based questions and PDFs of Study of Compounds-Nitric Acid: <a href=\"https:\/\/cisceboard.org\/\" target=\"_blank\" rel=\"noopener\">ICSE <\/a>Class 10 Chemistry (Concise\/Selina). However, the notes should only be treated as references, and changes should be made according to the needs of the students.<\/p>\n\n\n  <style>\r\n    .notice {\r\n      background: yellow;       \/* simple yellow background *\/\r\n      text-align: center;       \/* centre alignment *\/\r\n      padding: 12px 16px;\r\n      margin: 20px auto;\r\n      width: fit-content;       \/* shrink to text and centre via auto margins *\/\r\n      font-family: Arial, sans-serif;\r\n    }\r\n  <\/style>\r\n  <div class=\"notice\">\r\n    If you notice any errors in the notes, please mention them in the comments\r\n  <\/div>\r\n<nav id=\"toc\" class=\"toc-box\"><\/nav>\r\n<style>\r\n.toc-box{\r\n  border:1px solid #e5e7eb;\r\n  border-radius:8px;\r\n  background:#fff;\r\n  margin:20px 0;\r\n  font-family:Arial, Helvetica, sans-serif\r\n}\r\n.toc-header{\r\n  padding:10px 14px;\r\n  font-size:16px;\r\n  font-weight:600;\r\n  border-bottom:1px solid #eef2f7;\r\n  background:#f8fafc\r\n}\r\n.toc-content{\r\n  padding:12px 18px\r\n}\r\n\r\n\/* Base list *\/\r\n.toc-content ul{\r\n  margin:0 25px;\r\n  padding-left:0;\r\n  list-style:none\r\n}\r\n\r\n\/* Level-based bullets *\/\r\n.toc-content li{\r\n  position:relative;\r\n  margin:6px 0;\r\n  margin-left:6px;\r\n  line-height:1.5;\r\n\tlist-style:disc;\r\n}\r\n\r\n\/* H2 bullet \u25cf *\/\r\n.toc-content li.level-2{\r\n  list-style:disc;\r\n\t\r\n}\r\n\r\n\/* H3 bullet \u25cb *\/\r\n.toc-content li.level-3{\r\n  margin-left:26px;\r\n\tlist-style:disc;\r\n}\r\n\r\n\r\n\/* H4+ bullet \u2013 *\/\r\n.toc-content li.level-4{\r\n  margin-left:46px;\r\n\tlist-style:disc;\r\n}\r\n.toc-content li.level-5,\r\n.toc-content li.level-6{\r\n  margin-left:66px;\r\n\tlist-style:disc;\r\n}\r\n\r\n.toc-content a{\r\n  text-decoration:none;\r\n  color:#000\r\n}\r\n.toc-content a:hover{\r\n  text-decoration:underline\r\n}\r\n\r\nhtml{scroll-behavior:smooth}\r\nh1[id],h2[id],h3[id],h4[id],h5[id],h6[id]{\r\n  scroll-margin-top:110px\r\n}\r\n<\/style>\r\n\r\n<script>\r\ndocument.addEventListener('DOMContentLoaded', function () {\r\n\r\n  const toc = document.getElementById('toc');\r\n  if (!toc) return;\r\n\r\n  \/* MAIN CONTENT ONLY *\/\r\n  const content = document.querySelector('#pdf-content');\r\n\r\n  \/* EXCLUDE AREAS *\/\r\n  const excludeSelectors = `\r\n    .author, .byline, .entry-meta, .post-meta,\r\n    #comments, .comments-area, .comment-respond,\r\n    .comment-form, .comment-list,\r\n    .login, .login-required,\r\n    .sidebar, aside, footer, nav,\r\n    .widget, .widgets\r\n  `;\r\n\r\n  \/* TEXT TO IGNORE *\/\r\n  const ignoreText = [\r\n    'leave a comment',\r\n    'cancel reply',\r\n    'login required',\r\n    'get notes',\r\n    'ron\\'e dutta',\r\n    'comments'\r\n  ];\r\n\r\n  \r\nconst headings = [...content.querySelectorAll('h1,h2,h3,h4,h5,h6')]\r\n  .filter(h => !excludeSelectors || !h.closest(excludeSelectors))\r\n  .filter(h => {\r\n    const txt = h.textContent.trim().toLowerCase();\r\n    return txt.length > 0 && !ignoreText.some(t => txt.includes(t));\r\n  });\r\n\r\n\/\/alert(content);\r\n  if (!headings.length) {\r\n    toc.style.display = 'none';\r\n    return;\r\n  }\r\n\r\n  \/* UNIQUE IDs *\/\r\n  const used = {};\r\n  const slug = t => t.toLowerCase().trim()\r\n    .replace(\/[^a-z0-9\\s-]\/g, '')\r\n    .replace(\/\\s+\/g, '-');\r\n\r\n  headings.forEach(h => {\r\n    if (!h.id) {\r\n      let base = slug(h.textContent) || 'section';\r\n      used[base] = (used[base] || 0) + 1;\r\n      h.id = used[base] > 1 ? base + '-' + used[base] : base;\r\n    }\r\n  });\r\n\r\n  \/* BUILD TOC *\/\r\n  const ul = document.createElement('ul');\r\n\r\n  headings.forEach(h => {\r\n    const level = parseInt(h.tagName.substring(1));\r\n    if (level < 2) return; \/\/ skip H1 like your reference site\r\n\r\n    const li = document.createElement('li');\r\n    li.className = 'level-' + level;\r\n\r\n    const a = document.createElement('a');\r\n    a.href = '#' + h.id;\r\n    a.textContent = h.textContent.trim();\r\n\r\n    li.appendChild(a);\r\n    ul.appendChild(li);\r\n  });\r\n\r\n  toc.innerHTML = `\r\n    <div class=\"toc-header\">Table of Contents<\/div>\r\n    <div class=\"toc-content\"><\/div>\r\n  `;\r\n  toc.querySelector('.toc-content').appendChild(ul);\r\n\r\n});\r\n<\/script>\r\n\n\n\n\n<h3 class=\"wp-block-heading\" id=\"Summary\"><strong>Summary<\/strong><\/h3>\n\n\n\n<p>Nitric acid (HNO3) is a compound where nitrogen has a valency of five. It occurs in small amounts in rainwater after lightning and as mineral salts. Atmospheric lightning helps nitrogen and oxygen form nitric oxide, which becomes nitrogen dioxide. This gas dissolves in rainwater with oxygen to create nitric acid. This natural process is called atmospheric nitrogen fixation. Nitric acid was once called &#8220;aqua fortis,&#8221; meaning &#8220;strong water,&#8221; for its ability to react with many metals.<\/p>\n\n\n\n<p>In labs, nitric acid is made by heating potassium nitrate or sodium nitrate with concentrated sulphuric acid in a glass retort. The nitric acid vapor is cooled to become a liquid. This lab-made acid is often yellow due to dissolved nitrogen dioxide, a brown gas formed from some acid decomposing. Bubbling air through the warm acid or adding water can remove this color. All-glass apparatus is used, and heating is kept below 200\u00b0C.<\/p>\n\n\n\n<p>Industrially, the Ostwald process makes nitric acid. First, ammonia and air pass over a hot platinum catalyst, producing nitric oxide and heat. Second, nitric oxide cools and reacts with more air to form nitrogen dioxide. Third, nitrogen dioxide is absorbed in water in a tower, often packed with quartz, to form nitric acid. This acid can be concentrated further.<\/p>\n\n\n\n<p>Pure nitric acid is a colorless liquid; commercial acid can be yellowish. It has a sharp smell and sour taste. It is corrosive, staining skin yellow by reacting with proteins. Nitric acid is a strong acid, reacting with bases to form salts and water, and with carbonates to release carbon dioxide. A key feature is its strong oxidizing power. Its reaction with metals varies with acid concentration and the metal. Dilute acid usually gives metal nitrates and nitric oxide gas. Concentrated acid gives metal nitrates and nitrogen dioxide gas. Very dilute acid with magnesium or manganese can produce hydrogen. Metals like iron become passive with concentrated nitric acid due to a protective oxide layer. &#8220;Aqua regia,&#8221; a mix of nitric and hydrochloric acids, dissolves gold and platinum. The term &#8220;royal water&#8221; refers to its ability to dissolve these noble metals.<\/p>\n\n\n\n<p>Nitric acid is used to etch metals, purify gold, and as a rocket fuel oxidant. It is vital for making fertilizers like ammonium nitrate. It&#8217;s also used for explosives, dyes, plastics, and synthetic fibers. The brown ring test detects nitric acid or nitrates. Fresh iron(II) sulphate solution is added to the test sample, followed by concentrated sulphuric acid down the test tube&#8217;s side. A brown ring at the liquid junction confirms nitrate presence. Heating most metal nitrates releases brown nitrogen dioxide gas.<\/p>\n\n\n\n\n\n\n<h3 class=\"wp-block-heading\" id=\"Textbook_Total_History_solutions\"><strong>Workbook solutions (Concise\/Selina)<\/strong><\/h3>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"Intext_Questions_and_Answers_I\"><strong>Intext Questions and Answers I<\/strong><\/h3>\n\n\n\n<p><strong>1. Fill in the blank: Cold dil. nitric acid reacts with copper to form ____ (hydrogen, nitrogen dioxide, nitric oxide).<\/strong><\/p>\n\n\n\n<p><strong>Answer<\/strong>: Cold dil. nitric acid reacts with copper to form nitric oxide.<\/p>\n\n\n\n<p><strong>2. What is: (a) aqua fortis, (b) aqua regia (c) Fixation of Nitrogen?<\/strong><\/p>\n\n\n\n<p><strong>Answer<\/strong>: (a) Aqua fortis was the former name for nitric acid, meaning strong water.<br>(b) Aqua regia is a mixture formed when conc. nitric acid (1 part by volume) is mixed with conc. hydrochloric acid (3 parts by volume). It means royal water.<br>(c) Fixation of atmospheric nitrogen is the conversion of free atmospheric nitrogen into useful nitrogenous compounds in the soil.<\/p>\n\n\n\n<p><strong>3. During thunderstorm, rain water contains nitric acid. Explain with reactions.<\/strong><\/p>\n\n\n\n<p><strong>Answer<\/strong>: In the free state, nitric acid is found in rain water, where it occurs in traces after lightning. The formation of nitric acid in the atmosphere occurs as follows:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>During lightning discharge, the nitrogen present in the atmosphere reacts with the oxygen to form nitric oxide.<br>N\u2082 + O\u2082 &#8211;(3000\u00b0C)&#8211;&gt; 2NO<\/li>\n\n\n\n<li>Nitric oxide is further oxidised to nitrogen dioxide.<br>2NO + O\u2082 \u2192 2NO\u2082<\/li>\n\n\n\n<li>This nitrogen dioxide dissolves in atmospheric moisture or rain water in the presence of oxygen of the air and forms nitric acid in the free state.<br>4NO\u2082 + 2H\u2082O + O\u2082 \u2192 4HNO\u2083<\/li>\n<\/ul>\n\n\n\n<p><strong>4. Ammonia is used in the Ostwald process,<\/strong><\/p>\n\n\n\n<p><strong>(a) Give the source of reactants used in this process.<br>(b) Name the catalyst used in the process.<br>(c) Name the oxidising agent used in this process.<br>(d) What is the ratio of ammonia and air taken in this process?<br>(e) Why is quartz used in this process ?<\/strong><\/p>\n\n\n\n<p><strong>Answer<\/strong>: (a) The reactants used in the Ostwald process are a mixture of dry air (free from carbon dioxide and dust particles) and dry ammonia.<br>(b) The catalyst used in the process is platinum gauze.<br>(c) The oxidising agent used in this process is oxygen, present in the air.<br>(d) The ratio of dry air to dry ammonia taken in this process is 10 : 1 by volume.<br>(e) Quartz is used in this process because it is acid resistant and when packed in layers it helps in dissolving nitrogen dioxide uniformly in water in the absorption tower.<\/p>\n\n\n\n<p><strong>5. (a) Write a balanced chemical equation for the laboratory preparation of nitric acid.<\/strong><\/p>\n\n\n\n<p><strong>Answer<\/strong>: (a) A balanced chemical equation for the laboratory preparation of nitric acid is:<br>KNO\u2083 + H\u2082SO\u2084 (conc.) &#8211;(&lt;200\u00b0C)&#8211;&gt; KHSO\u2084 + HNO\u2083<br><strong><br>(b) In the preparation of nitric acid from KNO\u2083, concentrated hydrochloric acid is not used in place of concentrated sulphuric acid. Explain why ?<\/strong><\/p>\n\n\n\n<p><strong>Answer<\/strong>: (b) In the preparation of nitric acid from KNO\u2083, concentrated hydrochloric acid is not used in place of concentrated sulphuric acid because HCl is volatile and hence nitric acid vapours will carry HCl vapours.<br><strong><br>(c) Conc. nitric acid prepared in laboratory is yellow in colour. Why? How is this colour removed?<\/strong><\/p>\n\n\n\n<p><strong>Answer<\/strong>: (c) Conc. nitric acid prepared in the laboratory is slightly yellow. The yellow colour is due to dissolution of reddish brown coloured nitrogen dioxide gas in the acid. This gas is produced due to the thermal decomposition of a portion of nitric acid (4HNO\u2083 \u2192 2H\u2082O + 4NO\u2082 + O\u2082).<br>The yellow colour of the acid is removed:<br>(i) If dry air or CO\u2082 is bubbled through the yellow acid, the latter turns colourless because it drives out NO\u2082 from warm acid which is further oxidised to nitric acid.<br>(ii) By addition of excess of water, nitrogen dioxide gas dissolves in water and thus the yellow colour of the acid is removed.<br><strong><br>(d) Give reasons for the following: In the laboratory preparation of nitric acid, the mixture of concentrated sulphuric acid and sodium nitrate should not be heated very strongly above 200\u00b0C.<\/strong><\/p>\n\n\n\n<p><strong>Answer<\/strong>: (d) In the laboratory preparation of nitric acid, the mixture of concentrated sulphuric acid and sodium nitrate should not be heated very strongly above 200\u00b0C because sodium sulphate formed at higher temperature forms a hard crust which sticks to the walls of the retort and is difficult to remove, although the yield of HNO\u2083 is higher. The higher temperature (i) may damage the glass apparatus, (ii) decomposition of nitric acid can also occur, (iii) Wastage of fuel.<br><br><strong>6. (a) Nitric acid cannot be concentrated beyond 68% by the distillation of a dilute solution of HNO\u2083. State the reason.<br>(b) What is passive iron? How is passivity removed?<\/strong><\/p>\n\n\n\n<p><strong>Answer<\/strong>: (a) Nitric acid cannot be concentrated beyond 68% by the distillation of a dilute solution of HNO\u2083 because an aqueous solution of nitric acid (68% concentration) forms a constant boiling mixture at 121\u00b0C.<br>(b) Passive iron is iron that has become passive (inert) when treated with pure concentrated nitric acid. This is due to the formation of an extremely thin layer of insoluble metallic oxide (passivity) which stops the reaction.<br>Passivity can be removed by rubbing the surface layer with sand paper, or by treating with strong reducing agents.<\/p>\n\n\n\n<p><strong>7. Name the products formed when :<\/strong><strong><br><\/strong><strong>(a) carbon and conc. nitric acid is heated,<\/strong><strong><br><\/strong><strong>(b) dilute HNO\u2083 is added to copper.<\/strong><\/p>\n\n\n\n<p><strong>Answer<\/strong>: (a) When carbon and conc. nitric acid are heated, the products formed are carbon dioxide (CO\u2082), water (2H\u2082O), and nitrogen dioxide (4NO\u2082).<br>(b) When dilute HNO\u2083 is added to copper, the products formed are copper(II) nitrate (3Cu(NO\u2083)\u2082), water (4H\u2082O), and nitric oxide (2NO).<\/p>\n\n\n\n<p><strong>8. Give two chemical equations for each of the following:<\/strong><\/p>\n\n\n\n<p><strong>(a) Reactions of nitric acid with non-metals.<br>(b) Nitric acid showing as acidic character.<br>(c) Nitric acid acting as oxidising agent.<\/strong><\/p>\n\n\n\n<p><strong>Answer<\/strong>: (a) Two chemical equations for reactions of nitric acid with non-metals are:<br>1. C + 4HNO\u2083 [conc.] \u2192 CO\u2082 + 2H\u2082O + 4NO\u2082 (Reaction with Carbon)<br>2. S + 6HNO\u2083 [conc.] \u2192 H\u2082SO\u2084 + 2H\u2082O + 6NO\u2082 (Reaction with Sulphur)<\/p>\n\n\n\n<p>(b) Two chemical equations for nitric acid showing as acidic character are:<br>1. HNO\u2083(aq) \u21cc H\u207a + NO\u2083\u207b (Ionisation in aqueous solution)<br>2. CuO + 2HNO\u2083 \u2192 Cu(NO\u2083)\u2082 + H\u2082O (Reaction with a metallic oxide, e.g., copper(II) oxide, to form salt and water)<\/p>\n\n\n\n<p>(c) Two chemical equations for nitric acid acting as an oxidising agent are:<br>1. 2HNO\u2083 (conc.) \u2192 2NO\u2082 + H\u2082O + [O] (Decomposition to produce nascent oxygen)<br>2. Cu + 4HNO\u2083 (conc.) \u2192 Cu(NO\u2083)\u2082 + 2H\u2082O + 2NO\u2082 (Oxidation of a metal, e.g., copper)<\/p>\n\n\n\n<p><strong>9. Write balanced equations and name the products formed when:<br>(a) sodium hydrogen carbonate is added to nitric acid,<\/strong><\/p>\n\n\n\n<p><strong>Answer<\/strong>: When sodium hydrogen carbonate is added to nitric acid:<br>NaHCO\u2083 + HNO\u2083 \u2192 NaNO\u2083 + H\u2082O + CO\u2082\u2191<br>The products formed are sodium nitrate (NaNO\u2083), water (H\u2082O), and carbon dioxide (CO\u2082).<br><strong><br>(b) cupric oxide reacts with nitric acid,<\/strong><\/p>\n\n\n\n<p><strong>Answer<\/strong>: When cupric oxide reacts with nitric acid:<br>CuO + 2HNO\u2083 \u2192 Cu(NO\u2083)\u2082 + H\u2082O<br>The products formed are copper(II) nitrate (Cu(NO\u2083)\u2082) and water (H\u2082O).<br><strong><br>(c) zinc reacts with dilute nitric acid,<\/strong><\/p>\n\n\n\n<p><strong>Answer<\/strong>: When zinc reacts with dilute nitric acid:<br>3Zn + 8HNO\u2083 \u2192 3Zn(NO\u2083)\u2082 + 4H\u2082O + 2NO<br>The products formed are zinc nitrate (3Zn(NO\u2083)\u2082), water (4H\u2082O), and nitric oxide (2NO).<br><strong><br>(d) concentrated nitric acid is heated.<\/strong><\/p>\n\n\n\n<p><strong>Answer<\/strong>: When concentrated nitric acid is heated:<br>4HNO\u2083 &#8211;(\u0394)&#8211;&gt; 2H\u2082O + 4NO\u2082 + O\u2082<br>The products formed are water (2H\u2082O), nitrogen dioxide (4NO\u2082), and oxygen (O\u2082).<\/p>\n\n\n\n<p><strong>10. How will you prepare the following from nitric acid ?<br>(a) Sodium nitrate<\/strong><br><br><strong>Answer<\/strong>:  (a) Sodium nitrate can be prepared from nitric acid by reacting nitric acid with sodium hydroxide or sodium carbonate:<br>NaOH + HNO\u2083 \u2192 NaNO\u2083 + H\u2082O<br>or Na\u2082CO\u2083 + 2HNO\u2083 \u2192 2NaNO\u2083 + H\u2082O + CO\u2082\u2191<br><strong><br>(b) Copper nitrate<\/strong><\/p>\n\n\n\n<p><strong>Answer<\/strong>:  (b) Copper nitrate can be prepared from nitric acid by reacting nitric acid with copper metal, copper oxide, or copper carbonate:<br>3Cu + 8HNO\u2083 (dilute) \u2192 3Cu(NO\u2083)\u2082 + 4H\u2082O + 2NO<br>or CuO + 2HNO\u2083 \u2192 Cu(NO\u2083)\u2082 + H\u2082O<br><strong><br>(c) Lead nitrate<\/strong><\/p>\n\n\n\n<p><strong>Answer<\/strong>:  (c) Lead nitrate can be prepared from nitric acid by reacting nitric acid with lead metal or lead oxide. For example, with lead metal (similar to copper):<br>3Pb + 8HNO\u2083 (dilute) \u2192 3Pb(NO\u2083)\u2082 + 4H\u2082O + 2NO (This specific reaction for lead is a general application of nitric acid&#8217;s properties with metals, as detailed for copper and zinc).<br><strong><br>(d) Magnesium nitrate<\/strong><\/p>\n\n\n\n<p><strong>Answer<\/strong>: (d) Magnesium nitrate can be prepared from nitric acid by reacting very dilute nitric acid with magnesium metal or nitric acid with magnesium hydroxide:<br>Mg + 2HNO\u2083 (V. dilute) \u2192 Mg(NO\u2083)\u2082 + H\u2082<br>or Mg(OH)\u2082 + 2HNO\u2083 \u2192 Mg(NO\u2083)\u2082 + 2H\u2082O<br><strong><br>(e) Ferric nitrate<\/strong><\/p>\n\n\n\n<p><strong>Answer<\/strong>: (e) Ferric nitrate can be prepared from nitric acid by reacting concentrated nitric acid with iron metal or nitric acid with ferric hydroxide:<br>Fe + 6HNO\u2083 (conc.) \u2192 Fe(NO\u2083)\u2083 + 3H\u2082O + 3NO\u2082<br>or Fe(OH)\u2083 + 3HNO\u2083 \u2192 Fe(NO\u2083)\u2083 + 3H\u2082O<br><strong><br>(f) Aqua regia<\/strong><\/p>\n\n\n\n<p><strong>Answer<\/strong>: Aqua regia is prepared from nitric acid by mixing concentrated nitric acid (1 part by volume) with concentrated hydrochloric acid (3 parts by volume):<br>HNO\u2083 + 3HCl \u2192 NOCl + 2H\u2082O + 2[Cl]<\/p>\n\n\n\n<p><strong>11. Write equation for the following conversions A, B, C and D.<\/strong><\/p>\n\n\n\n<img decoding=\"async\" src=\"https:\/\/blogger.googleusercontent.com\/img\/b\/R29vZ2xl\/AVvXsEhi3oP2cufGfyuoOloKsysh-PDiVCrc3lEVKcJoHILRKmnxmiCUcBCEO5RNargL0WoaOwkPnVUlsqOv5f-4tRJg1iCMalVLMlxX1lOTGUeDm4vwEBRDeN8oe3jlyKTm0D68oE9j34Idr9-KZf35Jy1WJhxgJeYFmG2-gloiovHMw_myjTXYxelAoT5xdPhN\/s1200\/32.png\" style=\"max-width: 100%; height: auto; margin-bottom: 20px;\" \/>\n\n\n\n<p><strong>Answer<\/strong>:<br>A: Copper to Copper nitrate<br>3Cu + 8HNO\u2083 (dilute) \u2192 3Cu(NO\u2083)\u2082 + 4H\u2082O + 2NO<br>(Alternatively, with concentrated nitric acid: Cu + 4HNO\u2083 (conc.) \u2192 Cu(NO\u2083)\u2082 + 2H\u2082O + 2NO\u2082)<\/p>\n\n\n\n<p>B: Copper nitrate to Copper oxide<br>2Cu(NO\u2083)\u2082 &#8211;(\u0394)&#8211;&gt; 2CuO + 4NO\u2082 + O\u2082<\/p>\n\n\n\n<p>C: Copper to Copper oxide<br>2Cu + O\u2082 &#8211;(Heat)&#8211;&gt; 2CuO<br>(Oxygen for this reaction can be obtained from the decomposition of nitric acid: 4HNO\u2083 \u2192 2H\u2082O + 4NO\u2082 + O\u2082)<\/p>\n\n\n\n<p>D: Copper oxide to Copper<br>CuO + H\u2082 &#8211;(Heat)&#8211;&gt; Cu + H\u2082O<br>(This is a reduction reaction, typically not involving nitric acid as nitric acid is an oxidising agent.)<\/p>\n\n\n\n<p><strong>12. Correct the following, if required :<br>(a) HNO\u2083 is a strong reducing agent.<\/strong><\/p>\n\n\n\n<p><strong>Answers:<\/strong> HNO\u2083 is a strong reducing agent.<br><strong>Correction<\/strong>: HNO\u2083 is a strong <strong>oxidising<\/strong> agent. <br><strong><br>(b) NaNO\u2083 gives NO\u2082 and O\u2082 on heating.<\/strong><\/p>\n\n\n\n<p><strong>Answers: <\/strong>HNO\u2083 is a strong reducing agent.<br><strong>Correction<\/strong>: HNO\u2083 is a strong <strong>oxidising<\/strong> agent. <br><strong><br>(c) Constant boiling nitric acid contains 80% nitric acid by weight.<\/strong><\/p>\n\n\n\n<p><strong>Answers:<\/strong> HNO\u2083 is a strong reducing agent.<br><strong>Correction<\/strong>: HNO\u2083 is a strong <strong>oxidising<\/strong> agent. <br><strong><br>(d) Nitric acid remains colourless even when exposed to light.<\/strong><br><br><strong>Answers: <\/strong>HNO\u2083 is a strong reducing agent.<br><strong>Correction<\/strong>: HNO\u2083 is a strong <strong>oxidising<\/strong> agent.<br><strong><br>(e) Magnesium reacts with nitric acid to liberate hydrogen gas.<\/strong><\/p>\n\n\n\n<p><strong>Answer<\/strong>: Magnesium reacts with nitric acid to liberate hydrogen gas.<\/p>\n\n\n\n<p><strong>Correction (or clarification)<\/strong>: This statement is correct under specific conditions. Very dilute (about 1%) nitric acid reacts with magnesium at room temperature to give magnesium nitrate and hydrogen gas.<\/p>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"Intext_Questions_and_Answers_II\"><strong>MCQs<\/strong><\/h4>\n\n\n\n<p><strong>1. The nitrate salt which does not give a mixture of NO\u2082 and O\u2082 on heating is :<\/strong><\/p>\n\n\n\n<p>(a) AgNO\u2083<br>(b) KNO\u2083<br>(c) Cu(NO\u2083)\u2082<br>(d) Zn(NO\u2083)\u2082<\/p>\n\n\n\n<p><strong>Answer<\/strong>: (b) KNO\u2083<\/p>\n\n\n\n<p><strong>2. The chemical used in the brown ring test is :<\/strong><\/p>\n\n\n\n<p>(a) CuSO\u2084<br>(b) FeSO\u2084<br>(c) Fe\u2082(SO\u2084)\u2083<br>(d) ZnSO\u2084<\/p>\n\n\n\n<p><strong>Answer<\/strong>: (b) FeSO\u2084<\/p>\n\n\n\n<p><strong>3. Lead nitrate decomposes on heating to give :<\/strong><\/p>\n\n\n\n<p>(a) NO<br>(b) N\u2082O<br>(c) NO\u2082<br>(d) N\u2082O\u2085<\/p>\n\n\n\n<p><strong>Answer<\/strong>: (c) NO\u2082<\/p>\n\n\n\n<p><strong>4. In the laboratory preparation of nitric acid, nitre is heated with:<\/strong><\/p>\n\n\n\n<p>(a) conc. HCl<br>(b) conc. H\u2082SO\u2084<br>(c) dil. H\u2082SO\u2084<br>(d) conc. H\u2083PO\u2084<\/p>\n\n\n\n<p><strong>Answer<\/strong>: (b) conc. H\u2082SO\u2084<\/p>\n\n\n\n<p><strong>5. Nitric acid is manufactured by:<\/strong><\/p>\n\n\n\n<p>(a) Bayer&#8217;s process<br>(b) Haber&#8217;s process<br>(c) Ostwald process<br>(d) Contact process<\/p>\n\n\n\n<p><strong>Answer<\/strong>: (c) Ostwald process<\/p>\n\n\n\n<p><strong>6. The catalyst used in the manufacture of HNO\u2083 is :<\/strong><\/p>\n\n\n\n<p>(a) Pt<br>(b) V\u2082O\u2085 <br>(c) Fe<br>(d) Pd<\/p>\n\n\n\n<p><strong>Answer<\/strong>: (a) Pt<\/p>\n\n\n\n<p><strong>7. Cold and dilute HNO\u2083 reacts with Cu to give :<\/strong><\/p>\n\n\n\n<p>(a) NO\u2082 <br>(b) NO<br>(c) N\u2082<br>(d) O\u2082<\/p>\n\n\n\n<p><strong>Answer<\/strong>: (b) NO<\/p>\n\n\n\n<p><strong>8. The brown ring test is used for the detection of:<\/strong><\/p>\n\n\n\n<p>(a) CO\u2083\u00b2\u207b <br>(b) Cl\u207b <br>(c) NO\u2083\u207b<br>(d) SO\u2083\u00b2\u207b<\/p>\n\n\n\n<p><strong>Answer<\/strong>: (c) NO\u2083\u207b<\/p>\n\n\n\n<p><strong>9. Sulphur reacts with conc. HNO\u2083 to give :<\/strong><\/p>\n\n\n\n<p>(a) SO\u2082<br>(b) H\u2082<br>(c) H\u2082SO\u2084 <br>(d) H\u2082S<\/p>\n\n\n\n<p><strong>Answer<\/strong>: (c) H\u2082SO\u2084<\/p>\n\n\n\n<p><strong>10. The solvent for NO is :<\/strong><\/p>\n\n\n\n<p>(a) Freshly prepared FeSO\u2084 <br>(b) Fe\u2082(SO\u2084)\u2083<br>(c) FeCl\u2083<br>(d) FeCl\u2082<\/p>\n\n\n\n<p><strong>Answer<\/strong>: (a) Freshly prepared FeSO\u2084<\/p>\n\n\n\n<p><strong>11. The acid which can be used to etch designs on brassware is:<\/strong><\/p>\n\n\n\n<p>(a) HCl <br>(b) HNO\u2083 <br>(c) H\u2082SO\u2084<br>(d) H\u2082CO\u2083<\/p>\n\n\n\n<p><strong>Answer<\/strong>: (b) HNO\u2083<\/p>\n\n\n\n<p><strong>12. HNO\u2083 is kept in reagent bottles because it is :<\/strong><\/p>\n\n\n\n<p>(a) an oxidising agent <br>(b) a reducing agent<br>(c) hygroscopic in nature<br>(d) decomposed in the presence of light<\/p>\n\n\n\n<p><strong>Answer<\/strong>: (d) decomposed in the presence of light<\/p>\n\n\n\n<p><strong>13. The nitrate which does not leave any residue behind on heating is:<\/strong><\/p>\n\n\n\n<p>(a) NaNO\u2083<br>(b) NH\u2084NO\u2083<br>(c) AgNO\u2083<br>(d) Ca(NO\u2083)\u2082<\/p>\n\n\n\n<p><strong>Answer<\/strong>: (b) NH\u2084NO\u2083<\/p>\n\n\n\n<p><strong>14. On heating zinc nitrate, the products formed are zinc oxide, nitrogen dioxide and oxygen. Zinc oxide is :<\/strong><strong><br><\/strong>P a black solid<br>Q brown when hot, yellow when cold<br>R yellow when hot, white when cold<br>Which of the following is true ?<\/p>\n\n\n\n<p>(a) Only P<br>(b) Only Q<br>(c) Only R<br>(d) Both Q and R<\/p>\n\n\n\n<p><strong>Answer<\/strong>: (c) Only R<\/p>\n\n\n\n<p><strong>15. Assertion (A) : KNO\u2083 and conc. H\u2082SO\u2084 are the reactants for the preparation of nitric acid.<br>Reason (R): Conc. H\u2082SO\u2084 being a non volatile acid is required to prepare volatile acids.<\/strong><\/p>\n\n\n\n<p>(1) Both A and R are true and R is the correct explanation of A.<br>(2) Both A and R are true but R is not the correct explanation of A.<br>(3) A is true but R is false.<br>(4) A is false but R is true.<\/p>\n\n\n\n<p>(a) (1)<br>(b) (2) <br>(c) (3)<br>(d) (4)<\/p>\n\n\n\n<p><strong>Answer<\/strong>: (a) (1)<\/p>\n\n\n\n<p><strong>16. Assertion (A): Nitric acid prepared in the laboratory is yellow in colour.<\/strong><strong><br><\/strong><strong>Reason (R) : Brown gas is used in its preparation.<\/strong><\/p>\n\n\n\n<p>(1) Both A and R are true and R is the correct explanation of A.<br>(2) Both A and R are true but R is not the correct explanation of A.<br>(3) A is true but R is false.<br>(4) A is false but R is true.<\/p>\n\n\n\n<p>(a) (1)<br>(b) (2)<br>(c) (3)<br>(d) (4)<\/p>\n\n\n\n<p><strong>Answer<\/strong>: (c) (3)<\/p>\n\n\n\n<p><strong>17. Assertion (A): Catalytic oxidation of Ammonia does not require any external heat in Oswald process.<\/strong><strong><br><\/strong><strong>Reason (R): Catalytic oxidation of ammonia is an endothermic process.<\/strong><\/p>\n\n\n\n<p>(1) Both A and R are true and R is the correct explanation of A.<br>(2) Both A and R are true but R is not the correct explanation of A.<br>(3) A is true but R is false.<br>(4) A is false but R is true.<\/p>\n\n\n\n<p>(a) (1) <br>(b) (2)<br>(c) (3)<br>(d) (4)<\/p>\n\n\n\n<p><strong>Answer<\/strong>: (c) (3)<\/p>\n\n\n\n<p><strong>18. Assertion (A): The yellow colour of nitric acid is removed by using carbon dioxide gas or dry air.<\/strong><strong><br><\/strong><strong>Reason (R): Carbon dioxide gas or dry air drives away NO\u2082 gas from the warm nitric acid.<\/strong><\/p>\n\n\n\n<p>(1) Both A and R are true and R is the correct explanation of A.<br>(2) Both A and R are true but R is not the correct explanation of A.<br>(3) A is true but R is false.<br>(4) A is false but R is true.<\/p>\n\n\n\n<p>(a) (1)<br>(b) (2)<br>(c) (3)<br>(d) (4)<\/p>\n\n\n\n<p><strong>Answer<\/strong>: (a) (1)<\/p>\n\n\n\n<p><strong>19. Assertion (A): Nitric acid reacts with NaOH\/KOH to form salt and water.<\/strong><strong><br><\/strong><strong>Reason (R): Alkalies react with acids to form salt and water.<\/strong><\/p>\n\n\n\n<p>(1) Both A and R are true and R is the correct explanation of A.<br>(2) Both A and R are true but R is not the correct explanation of A.<br>(3) A is true but R is false.<br>(4) A is false but R is true.<\/p>\n\n\n\n<p>(a) (1)<br>(b) (2)<br>(c) (3)<br>(d) (4)<\/p>\n\n\n\n<p><strong>Answer<\/strong>: (a) (1)<\/p>\n\n\n\n<p><strong>20. Assertion (A): Cold and dilute nitric acid oxidise metals to their nitrates and nitric oxide.<\/strong><strong><br><\/strong><strong>Reason (R): Hot and concentrated nitric acid liberates nitrogen dioxide.<\/strong><\/p>\n\n\n\n<p>(1) Both A and R are true and R is the correct explanation of A.<br>(2) Both A and R are true but R is not the correct explanation of A.<br>(3) A is true but R is false.<br>(4) A is false but R is true.<\/p>\n\n\n\n<p>(a) (1) <br>(b) (2) <br>(c) (3)<br>(d) (4)<\/p>\n\n\n\n<p><strong>Answer<\/strong>: (b) (2)<\/p>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"Very_Short_Answer_Type\"><strong>Very Short Answer Type<\/strong><\/h4>\n\n\n\n<p><strong>1. Name:<\/strong><\/p>\n\n\n\n<p><strong>(a) a nitrate of metal which on heating does not give nitrogen dioxide.<\/strong><\/p>\n\n\n\n<p><strong>Answer:<\/strong> A nitrate of metal which on heating does not give nitrogen dioxide is potassium nitrate (KNO\u2083) or sodium nitrate (NaNO\u2083).<\/p>\n\n\n\n<p><strong>(b) a nitrate which on heating leaves no residue behind.<\/strong><\/p>\n\n\n\n<p><strong>Answer:<\/strong> A nitrate which on heating leaves no residue behind is ammonium nitrate (NH\u2084NO\u2083).<br><br><strong>(c) a metal nitrate which on heating is changed into metal oxide.<\/strong><\/p>\n\n\n\n<p><strong>Answer:<\/strong> A metal nitrate which on heating is changed into metal oxide is, for example, calcium nitrate [Ca(NO\u2083)\u2082], zinc nitrate [Zn(NO\u2083)\u2082], lead nitrate [Pb(NO\u2083)\u2082], or copper nitrate [Cu(NO\u2083)\u2082].<\/p>\n\n\n\n<p><strong>(d) a metal nitrate which on heating is changed into metal.<\/strong><\/p>\n\n\n\n<p><strong>Answer:<\/strong> A metal nitrate which on heating is changed into metal is silver nitrate (AgNO\u2083) or mercuric nitrate [Hg(NO\u2083)\u2082].<br><br><strong>(e) a solution which absorbs nitric oxide.<br><\/strong><br><strong>Answer:<\/strong> A solution which absorbs nitric oxide is a freshly prepared ferrous sulphate solution.<\/p>\n\n\n\n<p><strong>(f) the oxide of nitrogen which turns brown on exposure to air.<\/strong><\/p>\n\n\n\n<p><strong>Answer:<\/strong> The oxide of nitrogen which turns brown on exposure to air is nitric oxide (NO).<\/p>\n\n\n\n<p><strong>(g) the gas produced when copper reacts with conc. HNO3.<br><\/strong><br><strong>Answer:<\/strong>The gas produced when copper reacts with conc. HNO\u2083 is nitrogen dioxide (NO\u2082).<\/p>\n\n\n\n<p><strong>2. Identify the gas evolved when : <\/strong><br><strong>(a) Sulphur is treated with conc. nitric acid.<\/strong><\/p>\n\n\n\n<p><strong>Answer:<\/strong> When sulphur is treated with conc. nitric acid, the gas evolved is nitrogen dioxide (NO\u2082).<br><br><strong>(b) A few crystals of KNO3 are heated in a hard glass test tube.<\/strong><\/p>\n\n\n\n<p><strong>Answer:<\/strong> When a few crystals of KNO\u2083 are heated in a hard glass test tube, the gas evolved is oxygen (O\u2082).<\/p>\n\n\n\n<p><strong>3. Identify the acid :<\/strong><br><br><strong>(a) Which is used for the preparation of non-volatile acid.<br><br>Answer: <\/strong>The acid which is used for the preparation of a non-volatile acid (sulphuric acid from sulphur) is concentrated nitric acid.<br><br><strong>(b) The acid which is prepared by catalytic oxidation of ammonia.<\/strong><\/p>\n\n\n\n<p><strong>Answer:<\/strong> The acid which is prepared by catalytic oxidation of ammonia is nitric acid (HNO\u2083).<\/p>\n\n\n\n<p><strong>4. From the following list of substances, choose one substance in each case which matches the description given below: Ammonium nitrate, calcium hydrogen carbonate, copper carbonate, lead nitrate, potassium nitrate, sodium carbonate, sodium hydrogen carbonate, zinc carbonate.<\/strong><\/p>\n\n\n\n<p><strong>(a) Asubstancewhich gives off only oxygenwhen heated.<br><br>Answer: <\/strong> A substance which gives off only oxygen when heated is potassium nitrate.<br><br><strong>(b) A substance which on heating decomposes into dinitrogen oxide [nitrous oxide] and steam.<br><\/strong><br><strong>Answers:<\/strong> A substance which on heating decomposes into dinitrogen oxide [nitrous oxide] and steam is ammonium nitrate.<\/p>\n\n\n\n<p><strong>(c) A substance which gives off oxygen and nitrogen dioxide when heated.<\/strong><\/p>\n\n\n\n<p><strong>Answers: <\/strong>A substance which gives off oxygen and nitrogen dioxide when heated is lead nitrate.<br><br><strong>(d) A substance which on heating leaves yellow residue,<\/strong><\/p>\n\n\n\n<p><strong>Answers: <\/strong>A substance which on heating leaves a yellow residue is lead nitrate.<\/p>\n\n\n\n<p><strong>5. Complete the table :<\/strong><\/p>\n\n\n\n<div style=\"display: grid;grid-template-columns: repeat(4, 1fr);border: 1px solid #000;margin-bottom: 30px;font-family: Arial, sans-serif\">\n  <!-- Header Row -->\n  <div style=\"font-weight: bold;border-right: 1px solid #000;border-bottom: 1px solid #000;padding: 10px\">Name of Process<\/div>\n  <div style=\"font-weight: bold;border-right: 1px solid #000;border-bottom: 1px solid #000;padding: 10px\">Inputs<\/div>\n  <div style=\"font-weight: bold;border-right: 1px solid #000;border-bottom: 1px solid #000;padding: 10px\">Equation<\/div>\n  <div style=\"font-weight: bold;border-bottom: 1px solid #000;padding: 10px\">Output<\/div>\n\n  <!-- Row 1 -->\n  <div style=\"padding: 10px;border-right: 1px solid #000\"><\/div>\n  <div style=\"padding: 10px;border-right: 1px solid #000\">Ammonia + Air<\/div>\n  <div style=\"padding: 10px;border-right: 1px solid #000\"><\/div>\n  <div style=\"padding: 10px\">Nitric acid<\/div>\n<\/div>\n\n\n\n<p><strong>Answer:<\/strong><\/p>\n\n\n\n<div style=\"display: grid;grid-template-columns: repeat(4, 1fr);border: 1px solid #000;margin-bottom: 30px;font-family: Arial, sans-serif\">\n  <!-- Header Row -->\n  <div style=\"font-weight: bold;border-right: 1px solid #000;border-bottom: 1px solid #000;padding: 10px\">Name of Process<\/div>\n  <div style=\"font-weight: bold;border-right: 1px solid #000;border-bottom: 1px solid #000;padding: 10px\">Inputs<\/div>\n  <div style=\"font-weight: bold;border-right: 1px solid #000;border-bottom: 1px solid #000;padding: 10px\">Equation<\/div>\n  <div style=\"font-weight: bold;border-bottom: 1px solid #000;padding: 10px\">Output<\/div>\n\n  <!-- Row 1 -->\n  <div style=\"padding: 10px;border-right: 1px solid #000\">Ostwald Process<\/div>\n  <div style=\"padding: 10px;border-right: 1px solid #000\">Ammonia + Air<\/div>\n  <div style=\"padding: 10px;border-right: 1px solid #000;text-align: center\">4NH\u2083 + 5O\u2082 \u2192 4NO + 6H\u2082O + Heat (Pt catalyst)<\/div>\n  <div style=\"padding: 10px\">Nitric acid<\/div>\n<\/div>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"Short_Answer_Type\"><strong>Short Answer Type<\/strong><\/h4>\n\n\n\n<p><strong>1. Explain why<\/strong><br><br><strong>(a) Only all-glass apparatus should be used for the preparation of nitric acid by heating concentrated sulphuric acid and potassium nitrate.<\/strong><\/p>\n\n\n\n<p><strong>Answer: <\/strong>Only all-glass apparatus should be used for the preparation of nitric acid by heating concentrated sulphuric acid and potassium nitrate because nitric acid vapours attack rubber and cork.<\/p>\n\n\n\n<p><strong>(b) Nitric acid is kept in a reagent bottle for along time.<br><\/strong><br><strong>Answers: <\/strong> Nitric acid is kept in a reagent bottle for a long time, specifically in coloured bottles, because pure nitric acid is unstable to sunlight and decomposes. To avoid the decomposition, nitric acid is normally stored in coloured bottles. It is decomposed in the presence of light.<br><br><strong>(c) Iron is rendered passive with fuming HNO3. Give reason.<\/strong><\/p>\n\n\n\n<p><strong>Answers: <\/strong>Iron is rendered passive with fuming HNO\u2083. This is because metals like iron become passive (inert) when treated with pure concentrated nitric acid. It is due to the formation of an extremely thin layer of insoluble metallic oxide (passivity) which stops the reaction.<br><br><strong>(d) Dil. HNO3 is generally considered a typical acid but not so in the reaction with metals..<\/strong><\/p>\n\n\n\n<p><strong>Answers: <\/strong>Dil. HNO\u2083 is generally considered a typical acid but not so in its reaction with metals because, unlike typical acids, it does not liberate hydrogen. Dilute nitric acid is a powerful oxidising agent, and the nascent oxygen formed oxidises the hydrogen (that would have been formed) to water.<br><br><strong>(e) When it is left standing in a glass bottle concentrated nitric acid appears yellow.<\/strong><\/p>\n\n\n\n<p><strong>Answers: <\/strong>When it is left standing in a glass bottle, concentrated nitric acid appears yellow. This is because nitric acid decomposes, even at room temperature or in the presence of sunlight, to form nitrogen dioxide. The yellow colour is due to dissolved NO\u2082 in HNO\u2083. This nitrogen dioxide gas is produced due to the thermal decomposition of a portion of nitric acid (4HNO\u2083 \u2192 2H\u2082O + 4NO\u2082 + O\u2082).<\/p>\n\n\n\n<p><strong>2. A dilute acid B does not normally give hydrogen when reacted with metals but does give a gas when reacts with copper. Identify B. Write equation with copper.<\/strong><br><strong><br>Answer: <\/strong>Acid B is dilute nitric acid.<\/p>\n\n\n\n<p>The equation for the reaction of dilute nitric acid with copper is:<br>3Cu + 8HNO\u2083 (dilute) \u2192 3Cu(NO\u2083)\u2082 + 4H\u2082O + 2NO<\/p>\n\n\n\n<p><strong>3. State one observation:<\/strong><br><br><strong>(a) dilute nitric acid and copper carbonate.<br><br>Answer:<\/strong> When concentrated nitric acid is reacted with sulphur, reddish-brown fumes of nitrogen dioxide are evolved.<\/p>\n\n\n\n<p><strong>(b) oxidation of carbon with conc. HNO3.<br><\/strong><br><strong>Answer:<\/strong> When lead nitrate is heated strongly in a test tube, the colourless crystalline solid decrepitates, giving off reddish-brown fumes of nitrogen dioxide and leaving a yellow residue which fuses with glass.<\/p>\n\n\n\n<p><strong>(c) Laboratory preparation of nitric acid.<br><\/strong><br><strong>Answer:<\/strong> When zinc nitrate crystals are strongly heated, the very deliquescent crystals give off reddish-brown fumes of nitrogen dioxide and leave a residue which is yellow when hot and white when cold.<\/p>\n\n\n\n<p><strong>(d) Action of heat on a mixture of copper and nitric acid.<\/strong><\/p>\n\n\n\n<p><strong>Answer:<\/strong> When copper nitrate crystals are heated in a test tube, the blue crystalline solid gives off reddish-brown fumes of nitrogen dioxide and leaves a black residue.<\/p>\n\n\n\n<p><strong>4. What is the property of nitric acid which allows it to react with copper?<\/strong><br><strong><br>Answer: <\/strong>The property of nitric acid that allows it to react with copper is its oxidising property. Nitric acid is a powerful oxidising agent.<\/p>\n\n\n\n<p><strong>5. Give balanced equations for the following :<\/strong><br><br><strong>(a) dilute nitric acid and copper carbonate.<br><br>Answers: <\/strong>CuCO\u2083 + 2HNO\u2083 (dilute) \u2192 Cu(NO\u2083)\u2082 + H\u2082O + CO\u2082\u2191<br><br><strong>(b) Oxidation of carbon with conc. HNO\u2083:<br><\/strong><br><strong>Answers: <\/strong>C + 4HNO\u2083 (conc.) \u2192 CO\u2082 + 2H\u2082O + 4NO\u2082<br><br><strong>(c) Laboratory preparation of nitric acid (using sodium nitrate):<br><\/strong><br><strong>Answers: <\/strong>NaNO\u2083 + H\u2082SO\u2084 (conc.) &lt;200\u00b0C \u2192 NaHSO\u2084 + HNO\u2083<br><br><strong>(d) Action of heat on a mixture of copper and nitric acid (assuming concentrated nitric acid or hot dilute nitric acid):<br><\/strong><br><strong>Answers: <\/strong>Cu + 4HNO\u2083 (conc.) \u2192 Cu(NO\u2083)\u2082 + 2H\u2082O + 2NO\u2082<\/p>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"Long_Answer_Type\"><strong>Long Answer Type<\/strong><\/h4>\n\n\n\n<p><strong>1. X, Y and Z are three crystalline solids which are soluble in water and have a common anion. To help you to identify X, Y and Z, you are provided with the following experimental observations. Copy and complete the corresponding inferences in (a) to (e).<\/strong><\/p>\n\n\n\n<p><strong>Answer:<\/strong><strong><br><\/strong>(a) A reddish-brown gas is obtained when X, Y and Z are separately warmed with concentrated sulphuric acid and copper turning added to the mixture.<br>INFERENCE 1: The common anion is the <strong>nitrate<\/strong> ion.<\/p>\n\n\n\n<p>(b) When X is heated, it melts and gives off only one gas which re-lights a glowing splint.<br>INFERENCE 2: The cation in X is either <strong>K\u207a<\/strong> or <strong>Na\u207a<\/strong>.<\/p>\n\n\n\n<p>(c) The action of heat on Y produces a reddish-brown gas and a yellow residue which fuses with the glass of the test tube.<br>INFERENCE 3: The metal ion present in Y is the <strong>Pb\u00b2\u207a<\/strong> ion.<\/p>\n\n\n\n<p>(d) When Z is heated, it leaves no residue. Warming Z with sodium hydroxide solution liberates a gas which turns moist red litmus paper blue.<br>INFERENCE 4: Z contains the <strong>ammonium (NH\u2084\u207a)<\/strong> cation.<\/p>\n\n\n\n<p>(e) Write the equations for the following reactions:<br>(1) X and concentrated sulphuric acid (below 200\u00b0 C). (One equation only for either of the cations given in INFERENCE 2).<br>KNO\u2083 + H\u2082SO\u2084 (conc.) \u2192 KHSO\u2084 + HNO\u2083 (below 200\u00b0C)<br><em>or<\/em><em><br><\/em>NaNO\u2083 + H\u2082SO\u2084 (conc.) \u2192 NaHSO\u2084 + HNO\u2083 (below 200\u00b0C)<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(2) Action of heat on Y.<\/p>\n\n\n\n<p>2Pb(NO\u2083)\u2082 \u2192 2PbO + 4NO\u2082 + O\u2082<\/p>\n\n\n\n<p>(3) Concentrated nitric acid is added to copper turnings kept in a beaker.<\/p>\n\n\n\n<p>Cu + 4HNO\u2083 (conc.) \u2192 Cu(NO\u2083)\u2082 + 2H\u2082O + 2NO\u2082<\/p>\n\n\n\n<p><strong>2. The diagram given below is a representation of the Industrial preparation of Nitric acid by Ostwald&#8217;s process. With respect to the process, answer the following questions:<\/strong><\/p>\n\n\n\n<img decoding=\"async\" src=\"https:\/\/blogger.googleusercontent.com\/img\/b\/R29vZ2xl\/AVvXsEjbf-rVfaDa5W3EEJRXUk00HYHcfm4p3n5YBM-1bIMbujo4PQn3DRdVYUerrJY5V7T252-PjS8I3RblJo8PQ0qat9vdOMygDF0ULhaTIHqxrYgvMzOpIy3H8G97Ge8Z8JM4cA3HbMhH-UikkgqYN9RKm1ybMjU7QzMvzyFgc5Mwm9-c4cXnYgv_MseXFW_U\/s1200\/33.png\" style=\"max-width: 100%; height: auto; margin-bottom: 20px;\" \/>\n\n\n\n<p><strong>(a) Write the temperature and the catalyst required during the catalytic oxidation of ammonia.<br>(b) Give balanced chemical equation for the reaction occurring during the conversion of nitrogen dioxide to nitric acid.<\/strong><\/p>\n\n\n\n<p><strong>Answer: <\/strong>(a) The temperature and the catalyst required during the catalytic oxidation of ammonia are about 800\u00b0C and platinum gauze, respectively.<\/p>\n\n\n\n<p>(b) The balanced chemical equation for the reaction occurring during the conversion of nitrogen dioxide to nitric acid is:<br>4NO\u2082(g) + 2H\u2082O(l) + O\u2082(g) \u2192 4HNO\u2083 (aq.)<\/p>\n\n\n\n<p><strong>3. (a) Mention three important uses of nitric acid. Give the property of nitric acid involved in the use.<\/strong><\/p>\n\n\n\n<p><strong>Answer: <\/strong>Three important uses of nitric acid and the property involved are:<\/p>\n\n\n\n<p>(i) To etch designs on copper and brassware.<br>Reason: Nitric acid acts as a solvent for a large number of metals except noble metals.<br>(ii) To purify gold.<br>Reason: Gold may contain Cu, Ag, Zn, Pb, etc., as impurities which dissolve in nitric acid.<br>(iii) It acts as a rocket fuel oxidant.<\/p>\n\n\n\n<p><strong>(b) Explain with the help of a balanced equation, the brown ring test for nitric acid.<\/strong><\/p>\n\n\n\n<p><strong>Answer: <\/strong>To the aqueous solution of a nitrate or nitric acid:<\/p>\n\n\n\n<p>(i) Add freshly prepared saturated solution of iron [II] sulphate.<br>(ii) Now add conc. sulphuric acid carefully from the sides of the test tube, so that it should not fall dropwise in the test tube.<br>(iii) Cool the test tube in water.<br>(iv) A brown ring appears at the junction of the two liquids.<br>The reactions are:<br>6FeSO\u2084 + 3H\u2082SO\u2084 + 2HNO\u2083 \u2192 3Fe\u2082(SO\u2084)\u2083 + 4H\u2082O + 2NO<br>FeSO\u2084 + NO \u2192 FeSO\u2084\u00b7NO (Nitroso ferrous sulphate, a brown compound)<\/p>\n\n\n\n<p><strong>(c) Why is freshly prepared ferrous sulphate solution used for testing the nitrate radical in the brown ring test?<\/strong><\/p>\n\n\n\n<p><strong>Answer: <\/strong>A freshly prepared ferrous sulphate solution is used because on exposure to the atmosphere, it is oxidised to ferric sulphate which will not give the brown ring.<\/p>\n\n\n\n<p><strong>4. The action of heat on the blue crystalline solid X, gives a reddish brown gas Y, a gas which re-lights a glowing splint and leaves a black residue. When gas Z, which has a rotten egg smell, is passed through a solution of X, a black ppt. is formed.<\/strong><\/p>\n\n\n\n<p><strong>Answer: <\/strong>(a) X is Copper nitrate (Cu(NO\u2083)\u2082). Y is Nitrogen dioxide (NO\u2082). Z is Hydrogen sulphide (H\u2082S).<\/p>\n\n\n\n<p>(b) The equation for the action of heat on X is:<br>2Cu(NO\u2083)\u2082 \u2192 2CuO + 4NO\u2082 + O\u2082<\/p>\n\n\n\n<p>(c) The equation between solution of X and gas Z is:<br>Cu(NO\u2083)\u2082(aq) + H\u2082S(g) \u2192 CuS(s) + 2HNO\u2083(aq)<\/p>\n\n\n\n<p><strong>5. (a) Dilute nitric acid is generally considered a typical acid except for its reaction with metals. In what way is dilute nitric acid different from other acids when it reacts with metals?<\/strong><\/p>\n\n\n\n<p><strong>Answer: <\/strong>Dilute Nitric acid is generally considered a typical acid except for its reaction with metals since it does not liberate hydrogen. It is a powerful oxidising agent and the nascent oxygen formed oxidises the hydrogen to water. However, very dilute (about 1%) acid reacts with magnesium and manganese at room temperature to give their nitrates and hydrogen gas. Since the oxidising action of the acid is much reduced due to dilution.<\/p>\n\n\n\n<p><strong>(b) Write the equation for the reaction of dilute nitric acid and conc. nitric acid with copper.<\/strong><\/p>\n\n\n\n<p><strong>Answer: <\/strong>The equation for the reaction of dilute nitric acid with copper is:<br>3Cu + 8HNO\u2083 (dilute) \u2192 3Cu(NO\u2083)\u2082 + 4H\u2082O + 2NO<\/p>\n\n\n\n<p>The equation for the reaction of conc. nitric acid with copper is:<br>Cu + 4HNO\u2083 (conc.) \u2192 Cu(NO\u2083)\u2082 + 2H\u2082O + 2NO\u2082<\/p>\n\n\n\n<p><strong>6. The figure given below illustrates the apparatus used in the laboratory preparation of nitric acid.<\/strong><\/p>\n\n\n\n<img decoding=\"async\" src=\"https:\/\/blogger.googleusercontent.com\/img\/b\/R29vZ2xl\/AVvXsEgNAS89I7B7ZUeeE4OTPmP31y5jIroXCwPOMJ3TtD6WWCFqOqLpBu_XLgIS-BsEBWIRYyyF3GwgHfn_nJb5PG-dz-ry79NlQoHHnBr-UWtKJohBdhxRRiD_KAD6ZqapqGIgNfOY8PnSTFTp5IMBTRwUIRLIuuOoBaakvgVotfDhMJgUHAwz_LnUqVMgTw37\/s1200\/34.png\" style=\"max-width: 100%; height: auto; margin-bottom: 20px;\" \/>\n\n\n\n<p><strong>(a) Name A (a liquid), B (a solid) and C (a liquid). (Do not give the formulae).<br>(b) Write an equation to show how nitric acid undergoes decomposition.<br>(c) Write the equation for the reaction in which copper is oxidized by concentrated nitric acid.<\/strong><\/p>\n\n\n\n<p><strong>Answer: <\/strong>(a) A (a liquid) is Concentrated Sulphuric Acid. B (a solid) is Sodium or Potassium Nitrate. C (a liquid) is Nitric Acid.<\/p>\n\n\n\n<p>(b) An equation to show how nitric acid undergoes decomposition is:<br>4HNO\u2083 \u2192 2H\u2082O + 4NO\u2082 + O\u2082<\/p>\n\n\n\n<p>(c) The equation for the reaction in which copper is oxidized by concentrated nitric acid is:<br>Cu + 4HNO\u2083 (conc.) \u2192 Cu(NO\u2083)\u2082 + 2H\u2082O + 2NO\u2082<\/p>\n\n\n\n<p><strong>7. With respect to the brown ring test for nitrates, explain :<\/strong><\/p>\n\n\n\n<p><strong>(a) Freshly prepared ferrous sulphate is used.<\/strong><strong><br><\/strong><strong>(b) Brown ring disappear if the test tube is disturbed.<\/strong><strong><br><\/strong><strong>(c) Lead nitrate does not respond properly to the brown ring test.<\/strong><strong><br><\/strong><strong>(d) What is the name and formula of the brown ring formed ?<\/strong><\/p>\n\n\n\n<p><strong>Answer: <\/strong>(a) Freshly prepared ferrous sulphate is used because on exposure to the atmosphere, it is oxidised to ferric sulphate which will not give the brown ring.<\/p>\n\n\n\n<p>(b) The brown ring disappears if the test tube is disturbed because the brown ring of nitroso ferrous sulphate decomposes on disturbing the test tube. The heat evolved decomposes the unstable brown ring.<\/p>\n\n\n\n<p>(c) Lead nitrate does not respond properly to the brown ring test. Salt solutions forming insoluble sulphates interfere with the result of the Brown ring test.<\/p>\n\n\n\n<p>(d) The name of the brown ring formed is nitroso ferrous sulphate, and its formula is FeSO\u2084\u00b7NO.<\/p>\n\n\n\n<p><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Get notes, summary, questions and answers, MCQs, extras, competency-based questions and PDFs of Study of Compounds-Nitric Acid: ICSE Class 10 Chemistry (Concise\/Selina). However, the notes should only be treated as references, and changes should be made according to the needs of the students. Summary Nitric acid (HNO3) is a compound where nitrogen has a valency&hellip; <a class=\"more-link\" href=\"https:\/\/mockupbw.site\/2025\/onlinefreenotes\/study-of-compounds-nitric-acid-icse-class-10\/\">Continue reading <span class=\"screen-reader-text\">Study of Compounds-Nitric Acid: ICSE Class 10 Chemistry<\/span><\/a><\/p>\n","protected":false},"author":1044,"featured_media":28066,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[49,34],"tags":[28,85,29,86,87,30,32,33,35,36,88,37,1223,38],"class_list":["post-25588","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-icse","category-notes","tag-answers","tag-chemistry","tag-class-10","tag-competency-based","tag-concise","tag-extras","tag-icse","tag-notes","tag-pdf","tag-questions","tag-selina","tag-solutions","tag-study-of-compounds-c-nitric-acid","tag-summary","entry"],"acf":[],"_links":{"self":[{"href":"https:\/\/mockupbw.site\/2025\/onlinefreenotes\/wp-json\/wp\/v2\/posts\/25588","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mockupbw.site\/2025\/onlinefreenotes\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mockupbw.site\/2025\/onlinefreenotes\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mockupbw.site\/2025\/onlinefreenotes\/wp-json\/wp\/v2\/users\/1044"}],"replies":[{"embeddable":true,"href":"https:\/\/mockupbw.site\/2025\/onlinefreenotes\/wp-json\/wp\/v2\/comments?post=25588"}],"version-history":[{"count":2,"href":"https:\/\/mockupbw.site\/2025\/onlinefreenotes\/wp-json\/wp\/v2\/posts\/25588\/revisions"}],"predecessor-version":[{"id":29979,"href":"https:\/\/mockupbw.site\/2025\/onlinefreenotes\/wp-json\/wp\/v2\/posts\/25588\/revisions\/29979"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/mockupbw.site\/2025\/onlinefreenotes\/wp-json\/wp\/v2\/media\/28066"}],"wp:attachment":[{"href":"https:\/\/mockupbw.site\/2025\/onlinefreenotes\/wp-json\/wp\/v2\/media?parent=25588"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mockupbw.site\/2025\/onlinefreenotes\/wp-json\/wp\/v2\/categories?post=25588"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mockupbw.site\/2025\/onlinefreenotes\/wp-json\/wp\/v2\/tags?post=25588"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}