{"id":17238,"date":"2025-06-12T09:50:10","date_gmt":"2025-06-12T09:50:10","guid":{"rendered":"https:\/\/gaviki.com\/blog\/?p=17238"},"modified":"2025-06-12T09:50:15","modified_gmt":"2025-06-12T09:50:15","slug":"consider-the-reaction-n2-o2-2no","status":"publish","type":"post","link":"https:\/\/gaviki.com\/blog\/consider-the-reaction-n2-o2-2no\/","title":{"rendered":"Consider the reaction N2 + O2 = 2NO"},"content":{"rendered":"\n<p>Consider the reaction N2 + O2 = 2NO. What is the partial pressure of N2 under normal atmospheric pressure?<\/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<p>Under normal atmospheric conditions, the partial pressure of nitrogen gas (<strong>N\u2082<\/strong>) in air is approximately:<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p><strong>0.78 atm<\/strong><\/p>\n<\/blockquote>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">Explanation (\u2248300 words)<\/h3>\n\n\n\n<p>Air is a mixture of gases, primarily <strong>nitrogen (N\u2082)<\/strong> and <strong>oxygen (O\u2082)<\/strong>, with small amounts of other gases like argon and carbon dioxide. At <strong>normal atmospheric pressure<\/strong> (1 atmosphere or <strong>1 atm<\/strong>), each gas in the mixture contributes to the total pressure in proportion to its <strong>mole fraction<\/strong>, a concept explained by <strong>Dalton\u2019s Law of Partial Pressures<\/strong>.<\/p>\n\n\n\n<p>Dalton\u2019s Law states:<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p><strong>P\u209c = P\u2081 + P\u2082 + P\u2083 + \u2026 + P\u2099<\/strong><\/p>\n<\/blockquote>\n\n\n\n<p>Where:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>P\u209c<\/strong> is the total pressure,<\/li>\n\n\n\n<li><strong>P\u2081, P\u2082, \u2026<\/strong> are the partial pressures of the component gases.<\/li>\n<\/ul>\n\n\n\n<p>In dry air at sea level:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Nitrogen (N\u2082)<\/strong> makes up approximately <strong>78%<\/strong> of the air by volume (or mole fraction),<\/li>\n\n\n\n<li><strong>Oxygen (O\u2082)<\/strong> is about <strong>21%<\/strong>,<\/li>\n\n\n\n<li>The remaining 1% includes argon, carbon dioxide, etc.<\/li>\n<\/ul>\n\n\n\n<p>So, the partial pressure of nitrogen can be calculated by:<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p><strong>P(N\u2082) = Mole fraction of N\u2082 \u00d7 Total pressure<\/strong><br><strong>P(N\u2082) = 0.78 \u00d7 1 atm = 0.78 atm<\/strong><\/p>\n<\/blockquote>\n\n\n\n<p>This is the partial pressure of nitrogen in the air before the reaction:<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p><strong>N\u2082 + O\u2082 \u21cc 2NO<\/strong><\/p>\n<\/blockquote>\n\n\n\n<p>This reaction is important in atmospheric chemistry and combustion. It is <strong>endothermic<\/strong> and generally occurs at <strong>high temperatures<\/strong> (e.g., inside engines or lightning strikes), not under ambient conditions. Under normal temperature and pressure (STP), the formation of nitric oxide (NO) from nitrogen and oxygen is <strong>extremely slow<\/strong>, so atmospheric concentrations of NO are typically low unless energy is added.<\/p>\n\n\n\n<p>To summarize: Under standard atmospheric pressure, <strong>the partial pressure of nitrogen gas is 0.78 atm<\/strong>, reflecting its dominant presence in Earth&#8217;s atmosphere.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Consider the reaction N2 + O2 = 2NO. What is the partial pressure of N2 under normal atmospheric pressure? The correct answer and explanation is: Under normal atmospheric conditions, the partial pressure of nitrogen gas (N\u2082) in air is approximately: 0.78 atm Explanation (\u2248300 words) Air is a mixture of gases, primarily nitrogen (N\u2082) and [&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-17238","post","type-post","status-publish","format-standard","hentry","category-quiz-questions"],"_links":{"self":[{"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts\/17238","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=17238"}],"version-history":[{"count":1,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts\/17238\/revisions"}],"predecessor-version":[{"id":17240,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts\/17238\/revisions\/17240"}],"wp:attachment":[{"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/media?parent=17238"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/categories?post=17238"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/tags?post=17238"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}