{"id":28477,"date":"2025-06-20T12:37:29","date_gmt":"2025-06-20T12:37:29","guid":{"rendered":"https:\/\/gaviki.com\/blog\/?p=28477"},"modified":"2025-06-20T12:37:36","modified_gmt":"2025-06-20T12:37:36","slug":"an-iron-nail-rusts-when-exposed-to-oxygen","status":"publish","type":"post","link":"https:\/\/gaviki.com\/blog\/an-iron-nail-rusts-when-exposed-to-oxygen\/","title":{"rendered":"An iron nail rusts when exposed to oxygen"},"content":{"rendered":"\n<p>An iron nail rusts when exposed to oxygen. For the following reaction, 0.383 moles of iron are mixed with 0.502 moles of oxygen gas. What is the formula for the limiting reactant?<\/p>\n\n\n\n<p><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-vivid-cyan-blue-color\"><strong>The correct answer and explanation is:<\/strong><\/mark><\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Correct Answer: O\u2082 (oxygen gas) is the limiting reactant<\/strong><\/h3>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Explanation (300 words):<\/strong><\/h3>\n\n\n\n<p>When iron (Fe) rusts, it reacts with oxygen (O\u2082) to form iron(III) oxide (Fe\u2082O\u2083), commonly known as rust. The balanced chemical equation for this reaction is: 4Fe+3O2\u21922Fe2O34Fe + 3O_2 \\rightarrow 2Fe_2O_3<\/p>\n\n\n\n<p>This tells us the <strong>mole ratio<\/strong> of Fe to O\u2082 is <strong>4:3<\/strong>. That means 4 moles of iron react with 3 moles of oxygen gas.<\/p>\n\n\n\n<p>We are given:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>0.383 moles of <strong>Fe<\/strong><\/li>\n\n\n\n<li>0.502 moles of <strong>O\u2082<\/strong><\/li>\n<\/ul>\n\n\n\n<p>To determine the <strong>limiting reactant<\/strong>, we compare how much oxygen is needed to fully react with the given amount of iron.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">Step 1: <strong>How much O\u2082 is needed to react with 0.383 mol of Fe?<\/strong><\/h3>\n\n\n\n<p>Use the mole ratio from the balanced equation: O2&nbsp;needed=34\u00d70.383=0.28725&nbsp;mol\\text{O}_2 \\text{ needed} = \\frac{3}{4} \\times 0.383 = 0.28725 \\text{ mol}<\/p>\n\n\n\n<p>So, <strong>only 0.287 mol<\/strong> of O\u2082 is needed to fully react with 0.383 mol of Fe. But we have <strong>0.502 mol<\/strong> of O\u2082 available, which is <strong>more than enough<\/strong>.<\/p>\n\n\n\n<p>So iron <strong>is not<\/strong> the limiting reactant.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">Step 2: <strong>How much Fe is needed to react with 0.502 mol of O\u2082?<\/strong><\/h3>\n\n\n\n<p>Fe&nbsp;needed=43\u00d70.502=0.6693&nbsp;mol\\text{Fe needed} = \\frac{4}{3} \\times 0.502 = 0.6693 \\text{ mol}<\/p>\n\n\n\n<p>But we only have <strong>0.383 mol of Fe<\/strong>, which is <strong>less than required<\/strong>. So <strong>Fe runs out first<\/strong> if we try to use up all the oxygen.<\/p>\n\n\n\n<p>Oops! That means <strong>our earlier conclusion is incorrect<\/strong>. Let\u2019s correct it:<\/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>Correct Limiting Reactant: Iron (Fe)<\/strong><\/h3>\n\n\n\n<p>Iron is the <strong>limiting reactant<\/strong> because you need <strong>0.669 mol<\/strong> of Fe to react with all the oxygen, but you only have <strong>0.383 mol<\/strong>.<\/p>\n\n\n\n<p>Thus, <strong>Fe is the limiting reactant<\/strong>, not O\u2082.<\/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: Fe (iron) is the limiting reactant.<\/strong><\/h3>\n","protected":false},"excerpt":{"rendered":"<p>An iron nail rusts when exposed to oxygen. For the following reaction, 0.383 moles of iron are mixed with 0.502 moles of oxygen gas. What is the formula for the limiting reactant? The correct answer and explanation is: Correct Answer: O\u2082 (oxygen gas) is the limiting reactant Explanation (300 words): When iron (Fe) rusts, it [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-28477","post","type-post","status-publish","format-standard","hentry","category-quiz-questions"],"_links":{"self":[{"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts\/28477","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/comments?post=28477"}],"version-history":[{"count":1,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts\/28477\/revisions"}],"predecessor-version":[{"id":28482,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts\/28477\/revisions\/28482"}],"wp:attachment":[{"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/media?parent=28477"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/categories?post=28477"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/tags?post=28477"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}