{"id":206734,"date":"2025-04-08T07:59:08","date_gmt":"2025-04-08T07:59:08","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=206734"},"modified":"2025-04-08T07:59:10","modified_gmt":"2025-04-08T07:59:10","slug":"enough-of-a-monoprotic-acid-is-dissolved-in-water-to-produce-a-0-0192-m-solution-10","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/04\/08\/enough-of-a-monoprotic-acid-is-dissolved-in-water-to-produce-a-0-0192-m-solution-10\/","title":{"rendered":"Enough of a monoprotic acid is dissolved in water to produce a 0.0192 M solution"},"content":{"rendered":"\n
Enough of a monoprotic acid is dissolved in water to produce a 0.0192 M solution. The pH of the resulting solution is 2.53. Calculate the Ka for the acid.<\/p>\n\n\n\n
The correct answer and explanation is :<\/strong><\/mark><\/p>\n\n\n\n
To calculate the acid dissociation constant (Ka) for a monoprotic acid, we need to use the given pH value and concentration of the acid to find the concentrations of the dissociated species in the solution. Here\u2019s a step-by-step breakdown of how to solve this:<\/p>\n\n\n\n
Step 1: Understand the problem<\/h3>\n\n\n\n
\n
The acid is monoprotic, meaning it dissociates in water according to the following equation: [ HA \\rightarrow H^+ + A^- ]<\/li>\n\n\n\n
The initial concentration of the acid (HA) is 0.0192 M.<\/li>\n\n\n\n
The pH of the solution is 2.53, which will allow us to find the concentration of (H^+) (hydrogen ions).<\/li>\n<\/ul>\n\n\n\n
Step 2: Determine the concentration of (H^+) ions<\/h3>\n\n\n\n
The pH of the solution is given as 2.53. To find the concentration of (H^+), we use the equation: [ pH = -\\log[H^+] ] Rearranging to solve for ([H^+]): [ [H^+] = 10^{-pH} = 10^{-2.53} ] Using a calculator: [ [H^+] = 2.95 \\times 10^{-3} \\, M ]<\/p>\n\n\n\n
Step 3: Set up an ICE table<\/h3>\n\n\n\n
We now know that the concentration of (H^+) at equilibrium is (2.95 \\times 10^{-3}) M. We can use this information to set up an ICE (Initial, Change, Equilibrium) table for the dissociation of the acid:<\/p>\n\n\n\n
Species<\/th>
Initial (M)<\/th>
Change (M)<\/th>
Equilibrium (M)<\/th><\/tr><\/thead>
HA<\/td>
0.0192<\/td>
-x<\/td>
0.0192 – x<\/td><\/tr>
H\u207a<\/td>
0<\/td>
+x<\/td>
x<\/td><\/tr>
A\u207b<\/td>
0<\/td>
+x<\/td>
x<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
From the ICE table, we know that (x = [H^+] = 2.95 \\times 10^{-3}) M. So, the concentration of the dissociated acid (A\u207b) is also (2.95 \\times 10^{-3}) M.<\/p>\n\n\n\n
Step 4: Calculate the Ka<\/h3>\n\n\n\n
The acid dissociation constant (K_a) is given by the expression: [ K_a = \\frac{[H^+][A^-]}{[HA]} ] Substitute the values: [ K_a = \\frac{(2.95 \\times 10^{-3})(2.95 \\times 10^{-3})}{0.0192 – 2.95 \\times 10^{-3}} ] [ K_a = \\frac{8.70 \\times 10^{-6}}{0.01625} ] [ K_a = 5.36 \\times 10^{-4} ]<\/p>\n\n\n\n
Final Answer:<\/h3>\n\n\n\n
The acid dissociation constant, (K_a), for the acid is approximately (5.36 \\times 10^{-4})<\/strong>.<\/p>\n\n\n\n
Explanation:<\/h3>\n\n\n\n
To solve for (K_a), we first used the given pH to calculate the concentration of (H^+) ions. From there, we constructed an ICE table to represent the dissociation process, determining the concentrations of the acid (HA), hydrogen ions (H\u207a), and the conjugate base (A\u207b) at equilibrium. Finally, we applied the formula for (K_a), which relates these concentrations, and calculated the acid dissociation constant.<\/p>\n\n\n\n<\/figure>\n","protected":false},"excerpt":{"rendered":"
Enough of a monoprotic acid is dissolved in water to produce a 0.0192 M solution. The pH of the resulting solution is 2.53. Calculate the Ka for the acid. The correct answer and explanation is : To calculate the acid dissociation constant (Ka) for a monoprotic acid, we need to use the given pH value […]<\/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-206734","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/206734","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=206734"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/206734\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=206734"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=206734"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=206734"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
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<\/figure>\n","protected":false},"excerpt":{"rendered":"