{"id":218988,"date":"2025-05-24T18:35:16","date_gmt":"2025-05-24T18:35:16","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=218988"},"modified":"2025-05-24T18:35:18","modified_gmt":"2025-05-24T18:35:18","slug":"select-the-formula-for-magnesium-nitrite-trihydrate-and-determine-its-molecular-formula-mass","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/05\/24\/select-the-formula-for-magnesium-nitrite-trihydrate-and-determine-its-molecular-formula-mass\/","title":{"rendered":"Select the formula for magnesium nitrite trihydrate and determine its molecular (formula) mass."},"content":{"rendered":"\n<p>Be sure to answer all parts. Select the formula for magnesium nitrite trihydrate and determine its molecular (formula) mass.<\/p>\n\n\n\n<p>Formula:<\/p>\n\n\n\n<p>Mg(NO2)2\u00b73H2O<br>Molecular Mass: amu<\/p>\n\n\n\n<p><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-ast-global-color-1-color\">The Correct Answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n<p><strong>Formula:<\/strong><br><strong>Mg(NO\u2082)\u2082\u00b73H\u2082O<\/strong><\/p>\n\n\n\n<p><strong>Molecular Mass:<\/strong><br><strong>148.53 amu<\/strong><\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Explanation <\/strong><\/h3>\n\n\n\n<p>Magnesium nitrite trihydrate is an ionic compound consisting of magnesium cations, nitrite anions, and water of hydration. Understanding its formula and calculating its molecular mass involves knowledge of chemical nomenclature and atomic masses.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Step 1: Understanding the Formula<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Magnesium (Mg)<\/strong> is a Group 2 element, so it forms a +2 ion: <strong>Mg\u00b2\u207a<\/strong>.<\/li>\n\n\n\n<li><strong>Nitrite (NO\u2082\u207b)<\/strong> is a polyatomic ion with a \u22121 charge.<\/li>\n\n\n\n<li>To balance charges, two nitrite ions are needed for every magnesium ion:<br><strong>Mg\u00b2\u207a + 2 NO\u2082\u207b \u2192 Mg(NO\u2082)\u2082<\/strong><\/li>\n\n\n\n<li>The <strong>\u00b73H\u2082O<\/strong> indicates <strong>three water molecules<\/strong> of hydration, which are physically associated with the compound but not part of the ionic lattice. These are known as <strong>waters of crystallization<\/strong> or <strong>hydrates<\/strong>.<\/li>\n<\/ul>\n\n\n\n<p>Thus, the full formula is <strong>Mg(NO\u2082)\u2082\u00b73H\u2082O<\/strong>, representing <strong>magnesium nitrite trihydrate<\/strong>.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Step 2: Calculating Molecular Mass<\/strong><\/h3>\n\n\n\n<p>To calculate the molecular (formula) mass, sum the atomic masses of all atoms in the compound:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Mg<\/strong> = 24.31 amu<\/li>\n\n\n\n<li><strong>N<\/strong> = 14.01 amu \u00d7 2 = 28.02 amu<\/li>\n\n\n\n<li><strong>O<\/strong> in NO\u2082 = 16.00 amu \u00d7 4 = 64.00 amu<br>(There are 2 NO\u2082\u207b ions, each with 2 O atoms)<\/li>\n\n\n\n<li><strong>H\u2082O<\/strong> = (2 \u00d7 1.008) + 16.00 = 18.02 amu \u00d7 3 = 54.06 amu<\/li>\n<\/ul>\n\n\n\n<p><strong>Total Molecular Mass =<\/strong><br>24.31 (Mg) + 28.02 (N) + 64.00 (O from NO\u2082) + 54.06 (H\u2082O)<br>= <strong>170.39 amu<\/strong><\/p>\n\n\n\n<p><strong>Correction:<\/strong> Above sum gives <strong>170.39 amu<\/strong>, not 148.53 amu.<\/p>\n\n\n\n<p>Let&#8217;s re-calculate carefully:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Mg: 24.31<\/li>\n\n\n\n<li>N: 14.01 \u00d7 2 = 28.02<\/li>\n\n\n\n<li>O from NO\u2082: 16.00 \u00d7 4 = 64.00<\/li>\n\n\n\n<li>H: 1.008 \u00d7 6 = 6.048<\/li>\n\n\n\n<li>O from H\u2082O: 16.00 \u00d7 3 = 48.00<\/li>\n<\/ul>\n\n\n\n<p><strong>Total = 24.31 + 28.02 + 64.00 + 6.048 + 48.00 = 170.38 amu<\/strong><\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">\u2705 <strong>Final Answer:<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Formula:<\/strong> Mg(NO\u2082)\u2082\u00b73H\u2082O<\/li>\n\n\n\n<li><strong>Molecular Mass:<\/strong> <strong>170.38 amu<\/strong><\/li>\n<\/ul>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" src=\"https:\/\/learnexams.com\/blog\/wp-content\/uploads\/2025\/05\/image-406.png\" alt=\"\" class=\"wp-image-218989\"\/><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>Be sure to answer all parts. Select the formula for magnesium nitrite trihydrate and determine its molecular (formula) mass. Formula: Mg(NO2)2\u00b73H2OMolecular Mass: amu The Correct Answer and Explanation is: Formula:Mg(NO\u2082)\u2082\u00b73H\u2082O Molecular Mass:148.53 amu Explanation Magnesium nitrite trihydrate is an ionic compound consisting of magnesium cations, nitrite anions, and water of hydration. Understanding its formula and [&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-218988","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/218988","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=218988"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/218988\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=218988"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=218988"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=218988"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}