{"id":188792,"date":"2025-02-07T09:46:51","date_gmt":"2025-02-07T09:46:51","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=188792"},"modified":"2025-02-07T09:46:53","modified_gmt":"2025-02-07T09:46:53","slug":"consider-an-acetate-buffer-system-made-up-of-acetic-acid-and-sodium-acetate","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/02\/07\/consider-an-acetate-buffer-system-made-up-of-acetic-acid-and-sodium-acetate\/","title":{"rendered":"Consider an acetate buffer system made up of acetic acid and sodium acetate"},"content":{"rendered":"\n

Consider an acetate buffer system made up of acetic acid and sodium acetate, initially at the same pH as its pka (4.76). When small amount of base is added to this buffer which of the following reactions is most likely to occur which will prevent increase in pH of the buffer? O a. CH3COOH + N2OH – CH3C00+ H20 Ob. None of the above OC CH3CO0″ + HCI CH3COOH + Cr Od CH\u00c3\u00a1\u00c2\u00ba\u00c2\u00a1CO0 + NAOH – CH3COOH + Na* Oe. CH3COOH + HCI – CH3CO0 + H20<\/p>\n\n\n\n

The Correct Answer and Explanation is :<\/strong><\/mark><\/p>\n\n\n\n

The correct answer is d. CH\u2083COO\u207b + NaOH \u2192 CH\u2083COOH + Na\u207a<\/strong>.<\/p>\n\n\n\n

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

In an acetate buffer system, acetic acid (CH\u2083COOH) and sodium acetate (CH\u2083COONa) are in equilibrium. The pKa of acetic acid is 4.76, so the buffer will maintain a pH near this value when the concentrations of acetic acid and acetate ions are roughly equal.<\/p>\n\n\n\n

When a small amount of base (such as NaOH) is added to this buffer system, it will try to increase the pH. However, a buffer resists changes in pH by neutralizing the added base with its acidic component. In this case, the base (OH\u207b from NaOH) will react with the acidic component (CH\u2083COOH).<\/p>\n\n\n\n

The acetate ion (CH\u2083COO\u207b), which is the conjugate base of acetic acid, will accept the OH\u207b ion (from NaOH). This results in the formation of more acetic acid (CH\u2083COOH), and the pH increase is neutralized. This reaction can be represented as:<\/p>\n\n\n\n

CH\u2083COO\u207b + OH\u207b \u2192 CH\u2083COOH + H\u2082O<\/strong><\/p>\n\n\n\n

Thus, when NaOH is added, the acetate ions (CH\u2083COO\u207b) act to neutralize the hydroxide ions (OH\u207b), converting them into water and forming more acetic acid, which prevents a significant rise in pH. This is why the reaction that occurs in response to the addition of a base is CH\u2083COO\u207b + NaOH \u2192 CH\u2083COOH + Na\u207a<\/strong>.<\/p>\n\n\n\n

Let\u2019s briefly analyze the other options:<\/p>\n\n\n\n

    \n
  • a. CH\u2083COOH + N\u2082OH \u2192 CH\u2083COO\u207b + H\u2082O<\/strong>: This is an unlikely reaction in this context because N\u2082OH is not a relevant species in a typical buffer solution.<\/li>\n\n\n\n
  • b. None of the above<\/strong>: This is incorrect because option d describes the correct reaction.<\/li>\n\n\n\n
  • c. CH\u2083COO\u207b + HCl \u2192 CH\u2083COOH + Cl\u207b<\/strong>: This represents a neutralization between the acetate ion and HCl, which would be relevant when an acid is added, not a base.<\/li>\n\n\n\n
  • e. CH\u2083COOH + HCl \u2192 CH\u2083COO\u207b + H\u2082O<\/strong>: This is incorrect because HCl would donate H\u207a ions, not accept them.<\/li>\n<\/ul>\n\n\n\n

    In summary, the acetate buffer works by using the conjugate base (acetate) to neutralize any added acid or base, and the reaction that occurs when a base is added is CH\u2083COO\u207b + NaOH \u2192 CH\u2083COOH + Na\u207a<\/strong>, which prevents a significant pH increase.<\/p>\n","protected":false},"excerpt":{"rendered":"

    Consider an acetate buffer system made up of acetic acid and sodium acetate, initially at the same pH as its pka (4.76). When small amount of base is added to this buffer which of the following reactions is most likely to occur which will prevent increase in pH of the buffer? O a. CH3COOH + […]<\/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-188792","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/188792","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=188792"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/188792\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=188792"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=188792"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=188792"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}