{"id":206026,"date":"2025-03-26T10:15:15","date_gmt":"2025-03-26T10:15:15","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=206026"},"modified":"2025-03-26T10:15:17","modified_gmt":"2025-03-26T10:15:17","slug":"which-of-the-following-is-the-weakest-acid-2","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/03\/26\/which-of-the-following-is-the-weakest-acid-2\/","title":{"rendered":"Which of the following is the weakest acid"},"content":{"rendered":"\n<p>Which of the following is the weakest acid?<\/p>\n\n\n\n<p>A) HF (Ka for HF is 7.2 \u00d7 10-4)<\/p>\n\n\n\n<p>B) HCN (Ka for HCN is 4.9 \u00d7 10-10)<\/p>\n\n\n\n<p>C) HCNO (Ka for HCNO is 2 \u00d7 10-4)<\/p>\n\n\n\n<p>D) H3BO3 (Ka for H3BO3 is 5.4 \u00d7 10-10)<\/p>\n\n\n\n<p><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-ast-global-color-6-color\"><strong>The correct answer and explanation is :<\/strong><\/mark><\/p>\n\n\n\n<p>The strength of an acid is determined by its acid dissociation constant (Ka); the larger the Ka value, the stronger the acid, as it dissociates more readily in solution. Conversely, a smaller Ka value indicates a weaker acid.<\/p>\n\n\n\n<p>Let&#8217;s analyze the given acids and their Ka values:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>A) HF (Ka = 7.2 \u00d7 10\u207b\u2074):<\/strong> Hydrofluoric acid has a moderate Ka value, indicating it is a weak acid but not the weakest among the options.<\/li>\n\n\n\n<li><strong>B) HCN (Ka = 4.9 \u00d7 10\u207b\u00b9\u2070):<\/strong> Hydrocyanic acid has a significantly smaller Ka value, suggesting it is a weaker acid compared to HF.<\/li>\n\n\n\n<li><strong>C) HCNO (Ka = 2 \u00d7 10\u207b\u2074):<\/strong> Cyanic acid&#8217;s Ka value is similar to that of HF, indicating comparable acidity.<\/li>\n\n\n\n<li><strong>D) H\u2083BO\u2083 (Ka = 5.4 \u00d7 10\u207b\u00b9\u2070):<\/strong> Boric acid has a Ka value identical to that of HCN, making it equally weak.<\/li>\n<\/ul>\n\n\n\n<p>Among the provided acids, HCN and H\u2083BO\u2083 have the smallest Ka values (4.9 \u00d7 10\u207b\u00b9\u2070 and 5.4 \u00d7 10\u207b\u00b9\u2070, respectively), indicating they are the weakest acids in this list. However, since both have nearly identical Ka values, they are effectively the weakest acids among the options.<\/p>\n\n\n\n<p><em>Note: The slight difference in their Ka values (4.9 \u00d7 10\u207b\u00b9\u2070 for HCN and 5.4 \u00d7 10\u207b\u00b9\u2070 for H\u2083BO\u2083) is minimal, and for practical purposes, both can be considered equally weak acids.<\/em><\/p>\n\n\n\n<p>This image illustrates the relative strengths of various acids based on their Ka values, highlighting the position of HCN and H\u2083BO\u2083 among them.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" src=\"https:\/\/learnexams.com\/blog\/wp-content\/uploads\/2025\/03\/image-1489.png\" alt=\"\" class=\"wp-image-206027\"\/><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>Which of the following is the weakest acid? A) HF (Ka for HF is 7.2 \u00d7 10-4) B) HCN (Ka for HCN is 4.9 \u00d7 10-10) C) HCNO (Ka for HCNO is 2 \u00d7 10-4) D) H3BO3 (Ka for H3BO3 is 5.4 \u00d7 10-10) The correct answer and explanation is : The strength of an [&hellip;]<\/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-206026","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/206026","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=206026"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/206026\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=206026"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=206026"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=206026"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}