{"id":230998,"date":"2025-06-10T10:38:30","date_gmt":"2025-06-10T10:38:30","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=230998"},"modified":"2025-06-10T11:08:03","modified_gmt":"2025-06-10T11:08:03","slug":"hydrogen-sulfide-gas-is-bubbled-through-an-excess-of-potassium-hydroxide-solution","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/06\/10\/hydrogen-sulfide-gas-is-bubbled-through-an-excess-of-potassium-hydroxide-solution\/","title":{"rendered":"Hydrogen sulfide gas is bubbled through an excess of potassium hydroxide solution."},"content":{"rendered":"\n<p>Hydrogen sulfide gas is bubbled through an excess of potassium hydroxide solution. H2S + 2OH- \u00e2\u2020\u2019 S2- + 2H2O Write the balanced chemical equation excluding spectator ions. How do you get there from H2S + KOH -&gt; K2S + H2O?<\/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>Initial understanding:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Hydrogen sulfide (H\u2082S) reacts with potassium hydroxide (KOH) to produce potassium sulfide (K\u2082S) and water (H\u2082O).<\/li>\n\n\n\n<li>The given simplified unbalanced reaction is:<br><strong>H\u2082S + KOH \u2192 K\u2082S + H\u2082O<\/strong><\/li>\n<\/ul>\n\n\n\n<p><strong>Step 1: Write the unbalanced skeletal equation<\/strong><\/p>\n\n\n\n<p>H2S+KOH\u2192K2S+H2OH2\u200bS+KOH\u2192K2\u200bS+H2\u200bO<\/p>\n\n\n\n<p><strong>Step 2: Balance potassium (K) atoms<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>On the right, K\u2082S contains 2 K atoms.<\/li>\n\n\n\n<li>On the left, potassium appears only in KOH. To supply 2 K atoms, we need 2 KOH molecules.<\/li>\n<\/ul>\n\n\n\n<p>H2S+2\u2009KOH\u2192K2S+H2OH2\u200bS+2KOH\u2192K2\u200bS+H2\u200bO<\/p>\n\n\n\n<p><strong>Step 3: Check sulfur and hydrogen atoms<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Sulfur: 1 S on both sides.<\/li>\n\n\n\n<li>Hydrogen: 2 H in H\u2082S, and 2 H in 2 KOH (since each KOH has 1 H). On the product side, water has 2 H, matching the total H on the reactant side.<\/li>\n<\/ul>\n\n\n\n<p><strong>Step 4: Confirm the oxygen atoms<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Left: 2 KOH molecules contribute 2 O atoms.<\/li>\n\n\n\n<li>Right: 1 H\u2082O molecule has 1 O atom.<\/li>\n<\/ul>\n\n\n\n<p>This shows an imbalance in oxygen atoms. To balance oxygen, the product side should have 2 water molecules (since total O on reactant side is 2). So, update the product side:<\/p>\n\n\n\n<p>H2S+2\u2009KOH\u2192K2S+2\u2009H2OH2\u200bS+2KOH\u2192K2\u200bS+2H2\u200bO<\/p>\n\n\n\n<p>Now, oxygen atoms are balanced: 2 on each side.<\/p>\n\n\n\n<p><strong>Final balanced chemical equation:<\/strong><\/p>\n\n\n\n<p>H2S+2\u2009KOH\u2192K2S+2\u2009H2OH2\u200bS+2KOH\u2192K2\u200bS+2H2\u200bO<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">Explanation of the derivation:<\/h3>\n\n\n\n<p>This balanced chemical equation is consistent with the initial reaction of hydrogen sulfide with potassium hydroxide. The key steps involve:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Recognizing that 2 KOH molecules are needed to supply enough potassium ions (K\u207a) to form potassium sulfide (K\u2082S).<\/li>\n\n\n\n<li>Ensuring sulfur atoms are balanced: 1 S on each side.<\/li>\n\n\n\n<li>Balancing hydrogen atoms: 2 H from H\u2082S and 2 H from 2 KOH, resulting in 2 water molecules.<\/li>\n\n\n\n<li>Balancing oxygen atoms: both sides have 2 oxygen atoms.<\/li>\n<\/ul>\n\n\n\n<p><strong>Important note:<\/strong><br>The initial chemical equation involving spectator ions, <strong>H\u2082S + 2OH\u207b \u2192 S\u00b2\u207b + 2H\u2082O<\/strong>, is a net ionic form, focusing on the actual reacting species (hydroxide ions and H\u2082S). When considering the full molecular reaction with potassium ions, the balanced molecular equation includes KOH as shown above.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p><strong>Summary:<\/strong><br>Starting from the unbalanced reaction, by balancing K, H, and O atoms, we arrive at the balanced molecular equation:<\/p>\n\n\n\n<p>H2S+2\u2009KOH\u2192K2S+2\u2009H2OH2\u200bS+2KOH\u2192K2\u200bS+2H2\u200bO\u200b<\/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-banner4-840.jpeg\" alt=\"\" class=\"wp-image-230999\"\/><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>Hydrogen sulfide gas is bubbled through an excess of potassium hydroxide solution. H2S + 2OH- \u00e2\u2020\u2019 S2- + 2H2O Write the balanced chemical equation excluding spectator ions. How do you get there from H2S + KOH -&gt; K2S + H2O? The correct Answer and Explanation is: Initial understanding: Step 1: Write the unbalanced skeletal equation [&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-230998","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/230998","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=230998"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/230998\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=230998"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=230998"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=230998"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}