To calculate the molar mass of the diprotic acid, we first need to understand the neutralization reaction between the diprotic acid (H\u2082A) and sodium hydroxide (NaOH). The reaction can be represented as:H2A(aq)+2NaOH(aq)\u2192Na2A(aq)+2H2O(l)H_2A (aq) + 2 NaOH (aq) \\rightarrow Na_2A (aq) + 2 H_2O (l)H2\u200bA(aq)+2NaOH(aq)\u2192Na2\u200bA(aq)+2H2\u200bO(l)<\/p>\n\n\n\n
This equation shows that 1 mole of diprotic acid (H\u2082A) reacts with 2 moles of NaOH. The steps to find the molar mass of the diprotic acid are as follows:<\/p>\n\n\n\n
Step 1: Calculate the moles of NaOH used in the titration.<\/h3>\n\n\n\n
The molarity (M) of NaOH is given as 0.0311 M, and the volume used is 21.50 mL (which we convert to liters by dividing by 1000).Volume of NaOH=21.50\u2009mL=0.02150\u2009L\\text{Volume of NaOH} = 21.50 \\, \\text{mL} = 0.02150 \\, \\text{L}Volume of NaOH=21.50mL=0.02150L<\/p>\n\n\n\n
Now, calculate the moles of NaOH:Moles of NaOH=M\u00d7V=0.0311\u2009M\u00d70.02150\u2009L=0.00066965\u2009mol\\text{Moles of NaOH} = M \\times V = 0.0311 \\, \\text{M} \\times 0.02150 \\, \\text{L} = 0.00066965 \\, \\text{mol}Moles of NaOH=M\u00d7V=0.0311M\u00d70.02150L=0.00066965mol<\/p>\n\n\n\n
Step 2: Determine the moles of the diprotic acid.<\/h3>\n\n\n\n
Since the balanced equation shows that 2 moles of NaOH react with 1 mole of H\u2082A, the moles of the diprotic acid are half the moles of NaOH:Moles of H\u2082A=Moles of NaOH2=0.00066965\u2009mol2=0.000334825\u2009mol\\text{Moles of H\u2082A} = \\frac{\\text{Moles of NaOH}}{2} = \\frac{0.00066965 \\, \\text{mol}}{2} = 0.000334825 \\, \\text{mol}Moles of H\u2082A=2Moles of NaOH\u200b=20.00066965mol\u200b=0.000334825mol<\/p>\n\n\n\n
Step 3: Calculate the molar mass of the diprotic acid.<\/h3>\n\n\n\n
The mass of the diprotic acid is given as 0.0300 g. To find the molar mass (M), divide the mass of the acid by the moles of acid:Molar mass of H\u2082A=Mass of H\u2082AMoles of H\u2082A=0.0300\u2009g0.000334825\u2009mol=89.6\u2009g\/mol\\text{Molar mass of H\u2082A} = \\frac{\\text{Mass of H\u2082A}}{\\text{Moles of H\u2082A}} = \\frac{0.0300 \\, \\text{g}}{0.000334825 \\, \\text{mol}} = 89.6 \\, \\text{g\/mol}Molar mass of H\u2082A=Moles of H\u2082AMass of H\u2082A\u200b=0.000334825mol0.0300g\u200b=89.6g\/mol<\/p>\n\n\n\n
Final Answer:<\/h3>\n\n\n\n
The molar mass of the diprotic acid is 89.6 g\/mol<\/strong>.<\/p>\n\n\n\n This calculation uses stoichiometry to relate the volume and concentration of NaOH to the moles of the diprotic acid, which allows us to determine the molar mass.<\/p>\n\n\n\n Q2-A 0.0300 gm of a diprotic acid dissolved and diluted with distilled water then titrated with 21.50 mL of 0.0311 M NaOH. Calculate the molar mass of the diprotic acid. The Correct Answer and Explanation is: To calculate the molar mass of the diprotic acid, we first need to understand the neutralization reaction between the […]<\/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-246824","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/246824","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=246824"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/246824\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=246824"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=246824"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=246824"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}![\"\"](\"https:\/\/learnexams.com\/blog\/wp-content\/uploads\/2025\/07\/learnexams-banner5-950.jpeg\")
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