{"id":6849,"date":"2026-10-03T06:51:21","date_gmt":"2026-10-03T06:51:21","guid":{"rendered":"https:\/\/ksquareinstitute.in\/blog\/?p=6849"},"modified":"2026-10-03T07:07:36","modified_gmt":"2026-10-03T07:07:36","slug":"redox-reactions-neet-pyq-analysis","status":"publish","type":"post","link":"https:\/\/ksquareinstitute.in\/blog\/redox-reactions-neet-pyq-analysis\/","title":{"rendered":"Redox Reactions NEET PYQ Analysis"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">Redox Reactions is a short chapter with very predictable questions. Almost every one of them comes down to finding an oxidation number correctly. This redox reactions NEET PYQ analysis shows the question types NTA repeats, the rules that solve them, and the exceptions students forget in the exam hall.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"432\" src=\"https:\/\/ksquareinstitute.in\/blog\/wp-content\/uploads\/2026\/10\/Redox-Reactions-NEET-PYQ-Analysis-Zinc-and-Copper-1024x432.jpg\" alt=\"Redox reactions NEET PYQ analysis showing zinc in copper sulphate and a permanganate colour change\" class=\"wp-image-6850\" srcset=\"https:\/\/ksquareinstitute.in\/blog\/wp-content\/uploads\/2026\/10\/Redox-Reactions-NEET-PYQ-Analysis-Zinc-and-Copper-1024x432.jpg 1024w, https:\/\/ksquareinstitute.in\/blog\/wp-content\/uploads\/2026\/10\/Redox-Reactions-NEET-PYQ-Analysis-Zinc-and-Copper-300x127.jpg 300w, https:\/\/ksquareinstitute.in\/blog\/wp-content\/uploads\/2026\/10\/Redox-Reactions-NEET-PYQ-Analysis-Zinc-and-Copper-768x324.jpg 768w, https:\/\/ksquareinstitute.in\/blog\/wp-content\/uploads\/2026\/10\/Redox-Reactions-NEET-PYQ-Analysis-Zinc-and-Copper-1536x648.jpg 1536w, https:\/\/ksquareinstitute.in\/blog\/wp-content\/uploads\/2026\/10\/Redox-Reactions-NEET-PYQ-Analysis-Zinc-and-Copper.jpg 2048w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">For the full plan, see our <a href=\"https:\/\/ksquareinstitute.in\/blog\/physical-chemistry-for-neet-2027\">complete physical chemistry guide<\/a>. This article gives you the chapter-level detail.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Want to test yourself first? <a href=\"https:\/\/ksquareinstitute.com\/questions\/neet-previous-year-questions\/chemistry\/redox-reactions\/questions\/\" target=\"_blank\" rel=\"noopener\">Solve the Redox Reactions PYQs<\/a> for free, then use this guide to fix the gaps.<\/p>\n\n\n\n<div class=\"wp-block-rank-math-toc-block\" id=\"rank-math-toc\"><h2>Table of Contents<\/h2><nav><ul><li><a href=\"#why-redox-reactions-is-an-easy-scoring-chapter\">Why Redox Reactions Is an Easy Scoring Chapter<\/a><\/li><li><a href=\"#redox-reactions-neet-pyq-analysis-the-repeated-question-types\">Redox Reactions NEET PYQ Analysis: The Repeated Question Types<\/a><\/li><li><a href=\"#oxidation-number-rules-and-exceptions\">Oxidation Number: Rules and Exceptions<\/a><\/li><li><a href=\"#types-of-redox-reactions\">Types of Redox Reactions<\/a><\/li><li><a href=\"#balancing-redox-reactions-and-electrons-transferred\">Balancing Redox Reactions and Electrons Transferred<\/a><\/li><li><a href=\"#worked-pyq-pattern-questions\">Worked PYQ-Pattern Questions<\/a><\/li><li><a href=\"#common-traps-in-this-chapter\">Common Traps in This Chapter<\/a><\/li><li><a href=\"#practise-every-redox-reactions-pyq\">Practise Every Redox Reactions PYQ<\/a><\/li><li><a href=\"#conclusion\">Conclusion<\/a><\/li><li><a href=\"#\u2753-faq\">FAQ<\/a><\/li><\/ul><\/nav><\/div>\n\n\n\n<h2 id=\"why-redox-reactions-is-an-easy-scoring-chapter\" class=\"wp-block-heading\">Why Redox Reactions Is an Easy Scoring Chapter<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">NEET usually asks one question directly from this chapter, and sometimes two. The ideas also support Electrochemistry, d-Block and many Inorganic reactions, so the effort pays off more than once.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">In the NMC syllabus, the chapter sits in the unit &#8220;Redox Reactions and Electrochemistry&#8221;. See every unit in our <a href=\"https:\/\/ksquareinstitute.in\/blog\/neet-2027-chemistry-syllabus\">full Chemistry chapter list<\/a>, and check the <a href=\"https:\/\/ksquareinstitute.in\/blog\/neet-2027-syllabus-chapter-weightage\">NEET 2027 chapter weightage<\/a> for its share of the paper.<\/p>\n\n\n\n<h2 id=\"redox-reactions-neet-pyq-analysis-the-repeated-question-types\" class=\"wp-block-heading\">Redox Reactions NEET PYQ Analysis: The Repeated Question Types<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">When you sort a decade of NEET chemistry PYQs from this chapter, four question types cover almost everything.<\/p>\n\n\n\n<figure class=\"wp-block-table is-style-stripes\"><table class=\"has-white-background-color has-background has-border-color has-black-border-color\" style=\"border-width:2px\"><thead><tr><th>Question type<\/th><th>Frequency<\/th><th>What it tests<\/th><\/tr><\/thead><tbody><tr><td>Finding the oxidation state<\/td><td>Most frequent<\/td><td>Rules and exceptions for O, H and unusual compounds<\/td><\/tr><tr><td>Types of redox reactions<\/td><td>Very frequent<\/td><td>Spotting disproportionation<\/td><\/tr><tr><td>Oxidising and reducing agents<\/td><td>Regular<\/td><td>Which species is oxidised or reduced<\/td><\/tr><tr><td>Balancing and mole ratios<\/td><td>Regular<\/td><td>Electrons transferred, n-factor of KMnO\u2084 and K\u2082Cr\u2082O\u2087<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">For a quick warm-up before the full set, try these <a href=\"https:\/\/ksquareinstitute.in\/blog\/top-5-redox-reactions-questions\">five quick redox practice questions<\/a>.<\/p>\n\n\n\n<h2 id=\"oxidation-number-rules-and-exceptions\" class=\"wp-block-heading\">Oxidation Number: Rules and Exceptions<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>The sum of all oxidation states equals the charge on the species.<\/li>\n\n\n\n<li>Fluorine is always \u22121.<\/li>\n\n\n\n<li>Hydrogen is +1, except in metal hydrides such as NaH, where it is \u22121.<\/li>\n\n\n\n<li>Oxygen is \u22122, with three exceptions: \u22121 in peroxides (H\u2082O\u2082), \u2212\u00bd in superoxides (KO\u2082) and +2 in OF\u2082.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Values worth remembering:<\/p>\n\n\n\n<figure class=\"wp-block-table is-style-stripes\"><table class=\"has-white-background-color has-background has-border-color has-black-border-color\" style=\"border-width:2px\"><thead><tr><th>Compound<\/th><th>Element<\/th><th>Oxidation state<\/th><\/tr><\/thead><tbody><tr><td>KMnO\u2084<\/td><td>Mn<\/td><td>+7<\/td><\/tr><tr><td>K\u2082Cr\u2082O\u2087<\/td><td>Cr<\/td><td>+6<\/td><\/tr><tr><td>H\u2082SO\u2084<\/td><td>S<\/td><td>+6<\/td><\/tr><tr><td>Na\u2082S\u2082O\u2083<\/td><td>S<\/td><td>+2 (average)<\/td><\/tr><tr><td>Fe\u2083O\u2084<\/td><td>Fe<\/td><td>+8\/3 (average)<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">These calculations build on mole and stoichiometry skills, which our <a href=\"https:\/\/ksquareinstitute.in\/blog\/mole-concept-neet-pyq-analysis\">Mole Concept PYQ patterns<\/a> article covers.<\/p>\n\n\n\n<h2 id=\"types-of-redox-reactions\" class=\"wp-block-heading\">Types of Redox Reactions<\/h2>\n\n\n\n<figure class=\"wp-block-table is-style-stripes\"><table class=\"has-white-background-color has-background has-border-color has-black-border-color\" style=\"border-width:2px\"><thead><tr><th>Type<\/th><th>What happens<\/th><th>Example<\/th><\/tr><\/thead><tbody><tr><td>Combination<\/td><td>Elements combine<\/td><td>C + O\u2082 \u2192 CO\u2082<\/td><\/tr><tr><td>Decomposition<\/td><td>A compound breaks down<\/td><td>2H\u2082O \u2192 2H\u2082 + O\u2082<\/td><\/tr><tr><td>Displacement<\/td><td>One element replaces another<\/td><td>Zn + CuSO\u2084 \u2192 ZnSO\u2084 + Cu<\/td><\/tr><tr><td>Disproportionation<\/td><td>The same element is both oxidised and reduced<\/td><td>Cl\u2082 + 2NaOH \u2192 NaCl + NaOCl + H\u2082O<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">A disproportionation reaction is only possible when the element is in an intermediate oxidation state. That is why fluorine cannot disproportionate: it can only be 0 or \u22121.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Also remember:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>A species in its highest oxidation state can act only as an oxidising agent (for example, KMnO\u2084).<\/li>\n\n\n\n<li>A species in its lowest oxidation state can act only as a reducing agent (for example, H\u2082S). These ideas lead straight into cell reactions.<\/li>\n<\/ul>\n\n\n\n<h2 id=\"balancing-redox-reactions-and-electrons-transferred\" class=\"wp-block-heading\">Balancing Redox Reactions and Electrons Transferred<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">In the exam, you rarely need to balance a full equation. You need the number of electrons gained or lost.<\/p>\n\n\n\n<figure class=\"wp-block-table is-style-stripes\"><table class=\"has-white-background-color has-background has-border-color has-black-border-color\" style=\"border-width:2px\"><thead><tr><th>Oxidising agent<\/th><th>Medium<\/th><th>Product<\/th><th>Electrons gained<\/th><\/tr><\/thead><tbody><tr><td>KMnO\u2084<\/td><td>Acidic<\/td><td>Mn\u00b2\u207a<\/td><td>5<\/td><\/tr><tr><td>KMnO\u2084<\/td><td>Neutral<\/td><td>MnO\u2082<\/td><td>3<\/td><\/tr><tr><td>KMnO\u2084<\/td><td>Strongly basic<\/td><td>MnO\u2084\u00b2\u207b<\/td><td>1<\/td><\/tr><tr><td>K\u2082Cr\u2082O\u2087<\/td><td>Acidic<\/td><td>2Cr\u00b3\u207a<\/td><td>6<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">Electrons lost by the reducing agent must equal electrons gained by the oxidising agent. Use that single rule to get mole ratios when balancing redox reactions.<\/p>\n\n\n\n<h2 id=\"worked-pyq-pattern-questions\" class=\"wp-block-heading\">Worked PYQ-Pattern Questions<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Q1. What is the oxidation state of Cr in K\u2082Cr\u2082O\u2087?<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Answer: +6.<\/strong> 2(+1) + 2x + 7(\u22122) = 0, so x = +6.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Q2. Which of these shows disproportionation?<\/strong> (a) Zn + CuSO\u2084 \u2192 ZnSO\u2084 + Cu (b) Cl\u2082 + 2NaOH \u2192 NaCl + NaOCl + H\u2082O (c) 2H\u2082 + O\u2082 \u2192 2H\u2082O (d) CaCO\u2083 \u2192 CaO + CO\u2082<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Answer: (b).<\/strong> Chlorine goes from 0 to \u22121 in NaCl and to +1 in NaOCl.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Q3. How many moles of KMnO\u2084 are needed to oxidise 1 mole of Fe\u00b2\u207a in acidic medium?<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Answer: 1\/5 mole.<\/strong> Each MnO\u2084\u207b gains 5 electrons, and each Fe\u00b2\u207a loses 1 electron.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Q4. What is the oxidation state of oxygen in OF\u2082?<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Answer: +2.<\/strong> Fluorine is more electronegative than oxygen and is always \u22121.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Q5. In Zn + Cu\u00b2\u207a \u2192 Zn\u00b2\u207a + Cu, which species is the reducing agent?<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Answer: Zn.<\/strong> Zinc loses electrons and is oxidised, so it reduces Cu\u00b2\u207a.<\/p>\n\n\n\n<h2 id=\"common-traps-in-this-chapter\" class=\"wp-block-heading\">Common Traps in This Chapter<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Taking oxygen as \u22122 in peroxides, superoxides or OF\u2082<\/li>\n\n\n\n<li>Taking hydrogen as +1 in metal hydrides<\/li>\n\n\n\n<li>Mixing up the oxidising agent with the species that is oxidised<\/li>\n\n\n\n<li>Using 5 electrons for KMnO\u2084 in neutral or basic medium<\/li>\n\n\n\n<li>Calling CaCO\u2083 \u2192 CaO + CO\u2082 a redox reaction (no oxidation state changes)<\/li>\n<\/ul>\n\n\n\n<h2 id=\"practise-every-redox-reactions-pyq\" class=\"wp-block-heading\">Practise Every Redox Reactions PYQ<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">This redox reactions NEET PYQ analysis gives you the rules and exceptions. Practice makes them automatic. Every previous year question from this chapter is available chapter-wise, free:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\ud83d\udc49 <strong><a href=\"https:\/\/ksquareinstitute.com\/questions\/neet-previous-year-questions\/chemistry\/redox-reactions\/\" target=\"_blank\" rel=\"noopener\">Solve all Redox Reactions NEET PYQs<\/a><\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Write the oxidation state above each atom before reading the options. Most errors disappear once the numbers are on paper.<\/p>\n\n\n\n<h2 id=\"conclusion\" class=\"wp-block-heading\">Conclusion<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Redox Reactions rewards careful counting more than memory. Use this redox reactions NEET PYQ analysis to master the oxygen and hydrogen exceptions, the four reaction types and the electron counts for KMnO\u2084 and K\u2082Cr\u2082O\u2087. Then practise until you can assign oxidation states at a glance.<\/p>\n\n\n\n<h2 id=\"\u2753-faq\" class=\"wp-block-heading\">\u2753 FAQ<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Q: How many questions come from Redox Reactions in NEET?<\/strong> A: Usually one question, and sometimes two. Its concepts also appear in Electrochemistry and Inorganic Chemistry questions.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Q: What is a disproportionation reaction?<\/strong> A: It is a reaction in which the same element is oxidised and reduced at the same time. The element must start in an intermediate oxidation state.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Q: What is the oxidation state of oxygen in H\u2082O\u2082?<\/strong> A: It is \u22121. Oxygen is \u22122 in most compounds, but \u22121 in peroxides, \u2212\u00bd in superoxides and +2 in OF\u2082.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Q: How many electrons does KMnO\u2084 gain in acidic medium?<\/strong> A: Five electrons, because Mn changes from +7 to +2. In neutral medium it gains 3, and in strongly basic medium it gains 1.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Q: How should I revise this chapter for NEET?<\/strong> A: Use a redox reactions NEET PYQ analysis to list the repeated rules and exceptions, then solve past questions chapter-wise.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Q: Where can I practise Redox Reactions NEET PYQs for free?<\/strong> A: You can solve every previous year question from this chapter for free using the practice link in this article.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Redox Reactions is a short chapter with very predictable questions. Almost every one of them comes down to finding an oxidation number correctly. This redox reactions NEET PYQ analysis shows the question types NTA repeats, the rules that solve them, and the exceptions students forget in the exam hall. For the full plan, see our [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":6850,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[8,69,2],"tags":[2812,4117,4121,7,24,2328,4118,4116,4120,2322,4007,4119,4122],"class_list":["post-6849","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-study-tips","category-chemistry","category-neet","tag-class-11-chemistry","tag-disproportionation","tag-kmno4","tag-neet-2027","tag-neet-chemistry","tag-neet-pyq","tag-oxidation-number","tag-oxidation-state","tag-oxidising-agent","tag-physical-chemistry","tag-previous-year-questions","tag-redox-reactions","tag-reducing-agent"],"blocksy_meta":{"styles_descriptor":{"styles":{"desktop":"","tablet":"","mobile":""},"google_fonts":[],"version":8}},"_links":{"self":[{"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/posts\/6849","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/comments?post=6849"}],"version-history":[{"count":2,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/posts\/6849\/revisions"}],"predecessor-version":[{"id":6853,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/posts\/6849\/revisions\/6853"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/media\/6850"}],"wp:attachment":[{"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/media?parent=6849"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/categories?post=6849"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/tags?post=6849"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}