{"id":231916,"date":"2025-06-11T14:45:25","date_gmt":"2025-06-11T14:45:25","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=231916"},"modified":"2025-06-11T14:45:27","modified_gmt":"2025-06-11T14:45:27","slug":"the-molar-mass-of-hydrated-sodium-carbonate-is-268-g-mol","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/06\/11\/the-molar-mass-of-hydrated-sodium-carbonate-is-268-g-mol\/","title":{"rendered":"The molar mass of hydrated sodium carbonate is 268 g\/mol."},"content":{"rendered":"\n<p>The molar mass of hydrated sodium carbonate is 268 g\/mol. Calculate the number of moles of water of crystallization (x) if the formula for hydrated sodium carbonate is Na2CO3.xH2O.<\/p>\n\n\n\n<p><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-ast-global-color-0-color\">The Correct Answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n<p>To find the number of moles of water of crystallization (<strong>x<\/strong>) in the formula of hydrated sodium carbonate, <strong>Na\u2082CO\u2083\u00b7xH\u2082O<\/strong>, given that its <strong>molar mass is 268 g\/mol<\/strong>, we follow these steps:<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Step 1: Determine the molar mass of anhydrous sodium carbonate (Na\u2082CO\u2083)<\/h3>\n\n\n\n<p>Using atomic masses:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Na = 23 g\/mol<\/li>\n\n\n\n<li>C = 12 g\/mol<\/li>\n\n\n\n<li>O = 16 g\/mol<\/li>\n<\/ul>\n\n\n\n<p>Molar mass of Na\u2082CO\u2083 = (2 \u00d7 23) + 12 + (3 \u00d7 16)<br>= 46 + 12 + 48<br>= <strong>106 g\/mol<\/strong><\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Step 2: Let x be the number of water molecules.<\/h3>\n\n\n\n<p>Each water molecule (H\u2082O) has a molar mass of:<br>(2 \u00d7 1) + 16 = <strong>18 g\/mol<\/strong><\/p>\n\n\n\n<p>So, molar mass of Na\u2082CO\u2083\u00b7xH\u2082O = 106 + 18x<\/p>\n\n\n\n<p>We are told this equals 268 g\/mol:<\/p>\n\n\n\n<p><strong>106 + 18x = 268<\/strong><\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Step 3: Solve for x<\/h3>\n\n\n\n<p>18x = 268 \u2212 106<br>18x = 162<br>x = 162 \u00f7 18<br>x = <strong>9<\/strong><\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">Final Answer:<\/h3>\n\n\n\n<p><strong>x = 9<\/strong><br>So, the formula is <strong>Na\u2082CO\u2083\u00b79H\u2082O<\/strong><\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">Explanation <\/h3>\n\n\n\n<p>Hydrated salts are compounds that contain a specific number of water molecules loosely bonded within their crystal structure. These water molecules, known as <strong>water of crystallization<\/strong>, are integral to the composition and properties of the compound. In this case, we are asked to determine how many moles of water molecules are associated with each formula unit of <strong>sodium carbonate<\/strong>, Na\u2082CO\u2083, in its hydrated form.<\/p>\n\n\n\n<p>The compound is given as <strong>Na\u2082CO\u2083\u00b7xH\u2082O<\/strong>, and the total molar mass is provided as <strong>268 g\/mol<\/strong>. To find the value of x, we start by calculating the molar mass of the <strong>anhydrous<\/strong> part\u2014sodium carbonate (Na\u2082CO\u2083). By summing the atomic masses of its elements (2 sodium atoms, 1 carbon atom, and 3 oxygen atoms), we find that anhydrous sodium carbonate has a molar mass of <strong>106 g\/mol<\/strong>.<\/p>\n\n\n\n<p>Next, we recognize that the remaining mass must come from the x number of water molecules. Each H\u2082O has a molar mass of 18 g\/mol. Thus, the total mass of the hydrated compound can be expressed as:<br>106 + 18x = 268.<\/p>\n\n\n\n<p>Solving this equation yields <strong>x = 9<\/strong>, meaning that there are <strong>nine water molecules<\/strong> associated with each formula unit of sodium carbonate in the hydrated compound. Therefore, the full formula is <strong>Na\u2082CO\u2083\u00b79H\u2082O<\/strong>, known as <strong>sodium carbonate nonahydrate<\/strong>.<\/p>\n\n\n\n<p>This kind of calculation is essential in understanding the composition of hydrates and is widely used in chemistry to determine empirical formulas, calculate yields, and prepare accurate chemical solutions.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" src=\"https:\/\/learnexams.com\/blog\/wp-content\/uploads\/2025\/06\/learnexams-banner4-1003.jpeg\" alt=\"\" class=\"wp-image-231917\"\/><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>The molar mass of hydrated sodium carbonate is 268 g\/mol. Calculate the number of moles of water of crystallization (x) if the formula for hydrated sodium carbonate is Na2CO3.xH2O. The Correct Answer and Explanation is: To find the number of moles of water of crystallization (x) in the formula of hydrated sodium carbonate, Na\u2082CO\u2083\u00b7xH\u2082O, given [&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-231916","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/231916","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=231916"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/231916\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=231916"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=231916"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=231916"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}