{"id":218313,"date":"2025-05-23T15:08:54","date_gmt":"2025-05-23T15:08:54","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=218313"},"modified":"2025-05-23T15:08:56","modified_gmt":"2025-05-23T15:08:56","slug":"a-mixture-of-heptane-bp-98-c-and-1-propanol-bp-97-c-is-not-fully-resolved-on-a-column-of-se-30-but-is-easily-separated-on-a-column-of-degs","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/05\/23\/a-mixture-of-heptane-bp-98-c-and-1-propanol-bp-97-c-is-not-fully-resolved-on-a-column-of-se-30-but-is-easily-separated-on-a-column-of-degs\/","title":{"rendered":"A mixture of heptane (bp 98 c) and 1-propanol (bp 97 c) is not fully resolved on a column of SE-30 but is easily separated on a column of DEGs."},"content":{"rendered":"\n

A mixture of heptane (bp 98 c) and 1-propanol (bp 97 c) is not fully resolved on a column of SE-30 but is easily separated on a column of DEGs. Explain?<\/p>\n\n\n\n

The Correct Answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n

The correct answer:
The mixture of heptane and 1-propanol is not fully resolved on a column of SE-30 because SE-30 is a non-polar stationary phase, which does not effectively differentiate between compounds with similar boiling points but different polarities. In contrast, DEGs (diethylene glycol succinate) is a polar stationary phase that interacts more strongly with polar compounds like 1-propanol, allowing better separation from non-polar compounds like heptane.<\/strong><\/p>\n\n\n\n

\n\n\n\n

Detailed Explanation (\u2248300 words):<\/h3>\n\n\n\n

Gas chromatography (GC) separates compounds based on their volatility and interactions with the stationary phase in the column. Two key factors influencing separation are boiling point<\/strong> and polarity<\/strong>. While heptane and 1-propanol have nearly identical boiling points (98\u00b0C and 97\u00b0C, respectively), their chemical nature<\/strong> is quite different: heptane is non-polar<\/strong>, while 1-propanol is polar<\/strong> due to its hydroxyl (-OH) group.<\/p>\n\n\n\n

SE-30<\/strong> is a non-polar<\/strong> stationary phase made of polydimethylsiloxane. It interacts weakly with both heptane and 1-propanol, primarily via van der Waals forces. Because both compounds have similar volatilities and experience similarly weak interactions with SE-30, they elute at nearly the same time, making separation poor or unresolved.<\/p>\n\n\n\n

In contrast, DEGs (diethylene glycol succinate)<\/strong> is a polar<\/strong> stationary phase. It forms stronger dipole-dipole and hydrogen-bonding interactions<\/strong> with polar compounds like 1-propanol but interacts only weakly with non-polar compounds like heptane. This difference in interaction slows down 1-propanol significantly more than heptane<\/strong>, thereby increasing the retention time difference between the two and allowing for effective separation.<\/p>\n\n\n\n

This scenario illustrates a fundamental principle in gas chromatography: to separate components with similar boiling points but differing polarities, a stationary phase that can exploit those polarity differences (e.g., polar vs. non-polar) is crucial. Hence, DEGs<\/strong> provides superior separation in this case by leveraging the selectivity based on polarity<\/strong>, which SE-30 cannot offer.<\/p>\n\n\n\n

Thus, the resolution of heptane and 1-propanol is successful on DEGs due to its ability to discriminate based on polarity, not just volatility.<\/p>\n\n\n\n

\"\"<\/figure>\n","protected":false},"excerpt":{"rendered":"

A mixture of heptane (bp 98 c) and 1-propanol (bp 97 c) is not fully resolved on a column of SE-30 but is easily separated on a column of DEGs. Explain? The Correct Answer and Explanation is: The correct answer:The mixture of heptane and 1-propanol is not fully resolved on a column of SE-30 because […]<\/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-218313","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/218313","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=218313"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/218313\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=218313"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=218313"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=218313"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}