{"id":201992,"date":"2025-03-17T05:51:15","date_gmt":"2025-03-17T05:51:15","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=201992"},"modified":"2025-03-17T05:51:17","modified_gmt":"2025-03-17T05:51:17","slug":"arrange-the-following-halides-in-order-of-increasing-sn2-reactivity","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/03\/17\/arrange-the-following-halides-in-order-of-increasing-sn2-reactivity\/","title":{"rendered":"Arrange the following halides in order of increasing SN2 reactivity"},"content":{"rendered":"\n

Arrange the following halides in order of increasing SN2 reactivity :<\/p>\n\n\n\n

CH3Cl, CH3Br, CH3CH2Cl, (CH3)2 CHCl<\/p>\n\n\n\n

The correct answer and explanation is :<\/strong><\/mark><\/p>\n\n\n\n

Order of Increasing SN2 Reactivity:<\/h3>\n\n\n\n

[
(CH3)2CHCl < CH3CH2Cl < CH3Cl < CH3Br
]<\/p>\n\n\n\n

Explanation:<\/h3>\n\n\n\n

The S(_N)2 (bimolecular nucleophilic substitution)<\/strong> reaction occurs in a single step<\/strong> with backside attack<\/strong> by the nucleophile. The rate of an S(_N)2 reaction depends on the following key factors:<\/p>\n\n\n\n

1. Steric Hindrance:<\/strong><\/h4>\n\n\n\n
    \n
  • The nucleophile must approach the carbon attached to the leaving group from the opposite side.<\/li>\n\n\n\n
  • If the carbon is more substituted, steric hindrance increases, slowing down the reaction.<\/li>\n\n\n\n
  • In the given molecules:<\/li>\n\n\n\n
  • (CH\u2083)\u2082CHCl (Isopropyl chloride):<\/strong> A secondary<\/strong> alkyl halide \u2192 highest steric hindrance \u2192 least reactive<\/strong>.<\/li>\n\n\n\n
  • CH\u2083CH\u2082Cl (Ethyl chloride):<\/strong> A primary<\/strong> alkyl halide \u2192 lower steric hindrance than isopropyl chloride \u2192 more reactive.<\/li>\n\n\n\n
  • CH\u2083Cl (Methyl chloride):<\/strong> No steric hindrance since the carbon is directly bonded to only hydrogen atoms \u2192 even more reactive.<\/li>\n<\/ul>\n\n\n\n

    2. Leaving Group Ability:<\/strong><\/h4>\n\n\n\n
      \n
    • A better leaving group stabilizes the negative charge after departure, making the reaction faster.<\/li>\n\n\n\n
    • The halides follow this order of leaving group ability: I\u207b > Br\u207b > Cl\u207b > F\u207b<\/strong><\/li>\n\n\n\n
    • Since Br\u207b<\/strong> is a better leaving group than Cl\u207b<\/strong>, CH\u2083Br reacts faster than CH\u2083Cl.<\/li>\n<\/ul>\n\n\n\n

      Final Ranking (Increasing SN2 Reactivity):<\/strong><\/h3>\n\n\n\n

      (CH\u2083)\u2082CHCl<\/strong> (most sterically hindered, slowest)
      < CH\u2083CH\u2082Cl<\/strong> (primary, moderate steric hindrance)
      < CH\u2083Cl<\/strong> (methyl, no steric hindrance but poorer leaving group)
      < CH\u2083Br<\/strong> (methyl, best leaving group, fastest).<\/p>\n\n\n\n

      Thus, methyl bromide (CH\u2083Br) is the most reactive in S(_N)2.<\/strong><\/p>\n","protected":false},"excerpt":{"rendered":"

      Arrange the following halides in order of increasing SN2 reactivity : CH3Cl, CH3Br, CH3CH2Cl, (CH3)2 CHCl The correct answer and explanation is : Order of Increasing SN2 Reactivity: [(CH3)2CHCl < CH3CH2Cl < CH3Cl < CH3Br] Explanation: The S(_N)2 (bimolecular nucleophilic substitution) reaction occurs in a single step with backside attack by the nucleophile. The rate […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[25],"tags":[],"class_list":["post-201992","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/201992","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/comments?post=201992"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/201992\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=201992"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=201992"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=201992"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}