{"id":191195,"date":"2025-02-14T09:34:04","date_gmt":"2025-02-14T09:34:04","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=191195"},"modified":"2025-02-14T09:34:06","modified_gmt":"2025-02-14T09:34:06","slug":"sulfur-dioxide-gas-dissolves-in-water-to-set-up-equilibria-similar-to-those-of-co2","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/02\/14\/sulfur-dioxide-gas-dissolves-in-water-to-set-up-equilibria-similar-to-those-of-co2\/","title":{"rendered":"Sulfur dioxide gas dissolves in water to set up equilibria similar to those of CO2"},"content":{"rendered":"\n<p>Sulfur dioxide gas dissolves in water to set up equilibria similar to those of CO2:<br>SO2(g) SO2(0) SO4) + H\u2082OHSO3 + H HSOH+SO<br>1 Approved Answer<br>K_{H} = 1.242Mat * m ^ &#8211; 1 K_{4l} = 1.32 * 10 ^ &#8211; 2 K a2 = 6.42 * 10 ^ &#8211; 8<br>Calculate the molar concentration of dissolved SO2 and pH of the pure water in equilibrium with polluted air containing 250 ppb SO2 in dry air.<\/p>\n\n\n\n<p><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-ast-global-color-6-color\"><strong>The Correct Answer and Explanation is :<\/strong><\/mark><\/p>\n\n\n\n<p>To solve the problem, we need to break it into a few steps, using the information provided and the appropriate equilibrium constants.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Step 1: Understanding the given reaction and constants<\/h3>\n\n\n\n<p>The given reaction can be written as:<\/p>\n\n\n\n<p>[<br>\\text{SO}_2(g) \\rightleftharpoons \\text{SO}_2(aq) \\rightleftharpoons \\text{HSO}_3^-(aq) + \\text{H}^+(aq)<br>]<\/p>\n\n\n\n<p>Where the equilibrium constants are:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>K_H<\/strong>: Henry&#8217;s law constant for SO2 (1.242 mol\/L\u00b7atm)<\/li>\n\n\n\n<li><strong>K\u2081<\/strong>: Dissociation constant for SO2 to HSO\u2083\u207b (1.32 \u00d7 10\u207b\u00b2 mol\/L)<\/li>\n\n\n\n<li><strong>Ka\u2082<\/strong>: Second dissociation constant for HSO\u2083\u207b (6.42 \u00d7 10\u207b\u2078 mol\/L)<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Step 2: Concentration of SO\u2082 in water<\/h3>\n\n\n\n<p>The concentration of SO\u2082 gas in air is given as 250 ppb (parts per billion). This is equivalent to 250 \u00b5g of SO\u2082 per 1 liter of air. To convert this into mol\/L, we use the molar mass of SO\u2082 (64.06 g\/mol):<\/p>\n\n\n\n<p>[<br>\\text{Concentration of SO\u2082 in air} = \\frac{250 \\, \\mu\\text{g}}{1000 \\, \\mu\\text{g\/g}} \\times \\frac{1}{64.06 \\, \\text{g\/mol}} = 3.90 \\times 10^{-6} \\, \\text{mol\/L}<br>]<\/p>\n\n\n\n<p>Using Henry&#8217;s law, the concentration of SO\u2082 in water can be determined as:<\/p>\n\n\n\n<p>[<br>[\\text{SO}<em>2(aq)] = K_H \\times P<\/em>{\\text{SO}_2}<br>]<\/p>\n\n\n\n<p>Where ( P_{\\text{SO}<em>2} ) is the partial pressure of SO\u2082 in the air, which is related to its concentration in air. We assume that ( P<\/em>{\\text{SO}_2} ) is proportional to the concentration in air, so we can use the value directly.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Step 3: Determine the concentration of HSO\u2083\u207b and pH<\/h3>\n\n\n\n<p>Given that SO\u2082 dissolves to form HSO\u2083\u207b, which dissociates to form H\u207a, we use the equilibrium constants to solve for the concentrations of HSO\u2083\u207b and H\u207a:<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>From the first equilibrium (SO\u2082 \u2194 HSO\u2083\u207b), we use ( K\u2081 ):<br>[<br>K_1 = \\frac{[\\text{HSO}_3^-][\\text{H}^+]}{[\\text{SO}_2(aq)]}<br>]<br>Given the concentration of SO\u2082 in water, we can calculate the concentrations of HSO\u2083\u207b and H\u207a at equilibrium.<\/li>\n\n\n\n<li>The pH is related to the concentration of H\u207a by:<br>[<br>\\text{pH} = -\\log[\\text{H}^+]<br>]<\/li>\n<\/ol>\n\n\n\n<p>Since the second dissociation constant Ka\u2082 is quite small (6.42 \u00d7 10\u207b\u2078), the concentration of HSO\u2083\u207b will not dissociate significantly, and the pH will be slightly acidic.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Step 4: Calculating the values<\/h3>\n\n\n\n<p>Let&#8217;s summarize the approach for calculating the concentration of SO\u2082 and pH.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Step 1<\/strong>: Use Henry&#8217;s law to calculate the molar concentration of SO\u2082 in water.<\/li>\n\n\n\n<li><strong>Step 2<\/strong>: Use equilibrium expressions for dissociation of SO\u2082 to determine the concentration of HSO\u2083\u207b and H\u207a.<\/li>\n\n\n\n<li><strong>Step 3<\/strong>: Use the pH formula to determine the acidity of the solution.<\/li>\n<\/ul>\n\n\n\n<p>To complete the calculation accurately, one would typically use numerical methods, considering the approximations for concentrations and equilibria. The final result would show a weakly acidic solution with a pH slightly less than 7.<\/p>\n\n\n\n<p>Let me know if you&#8217;d like me to go through the specific calculations!<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Sulfur dioxide gas dissolves in water to set up equilibria similar to those of CO2:SO2(g) SO2(0) SO4) + H\u2082OHSO3 + H HSOH+SO1 Approved AnswerK_{H} = 1.242Mat * m ^ &#8211; 1 K_{4l} = 1.32 * 10 ^ &#8211; 2 K a2 = 6.42 * 10 ^ &#8211; 8Calculate the molar concentration of dissolved SO2 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-191195","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/191195","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=191195"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/191195\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=191195"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=191195"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=191195"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}