{"id":258944,"date":"2025-07-18T15:23:15","date_gmt":"2025-07-18T15:23:15","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=258944"},"modified":"2025-07-18T15:23:17","modified_gmt":"2025-07-18T15:23:17","slug":"benzophenone-infrared-spectrum","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/07\/18\/benzophenone-infrared-spectrum\/","title":{"rendered":"Benzophenone Infrared Spectrum"},"content":{"rendered":"\n

Transmitance 1.0 Benzophenone Infrared Spectrum 0.8 0.6 0.4 0.2 0.0 3500 3000 2500 2000 1500 1000 500 Wavenumbers (cm-1)<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

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

Correct Answer:<\/strong> This is the infrared (IR) spectrum of benzophenone.<\/p>\n\n\n\n

Explanation:<\/strong><\/p>\n\n\n\n

The provided image displays the infrared spectrum for benzophenone, a diaryl ketone. The key absorption bands in the spectrum directly correspond to the functional groups present in the benzophenone molecule, (C\u2086H\u2085)\u2082C=O.<\/p>\n\n\n\n

First, the region just above 3000 cm\u207b\u00b9 shows several sharp, medium intensity peaks, specifically around 3060 cm\u207b\u00b9. These absorptions are characteristic of C-H stretching vibrations where the carbon is sp\u00b2 hybridized, which is consistent with the hydrogen atoms attached to the two aromatic (phenyl) rings. The absence of significant peaks in the 2850-3000 cm\u207b\u00b9 range confirms the lack of aliphatic (sp\u00b3 hybridized) C-H bonds in the molecule.<\/p>\n\n\n\n

The most prominent and diagnostic feature in this spectrum is the very strong, sharp absorption at approximately 1660 cm\u207b\u00b9. This peak corresponds to the carbonyl (C=O) stretching vibration. For a simple aliphatic ketone, this peak typically appears around 1715 cm\u207b\u00b9. In benzophenone, the carbonyl group is conjugated with both aromatic rings. This conjugation allows for delocalization of the pi electrons, which weakens the C=O double bond and lowers its vibrational frequency, hence its appearance at a lower wavenumber like 1660 cm\u207b\u00b9.<\/p>\n\n\n\n

In the region from 1600 cm\u207b\u00b9 to 1450 cm\u207b\u00b9, there are several sharp peaks, including those near 1600 cm\u207b\u00b9 and 1450 cm\u207b\u00b9. These are characteristic skeletal C=C stretching vibrations within the aromatic rings.<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

Finally, the fingerprint region below 1500 cm\u207b\u00b9 contains complex information, but some features are highly informative. The strong, sharp absorptions around 750 cm\u207b\u00b9 and 700 cm\u207b\u00b9 are due to C-H out of plane bending vibrations. This specific pattern is a classic indicator of a monosubstituted benzene ring. Since benzophenone consists of two such phenyl groups attached to the carbonyl carbon, these peaks strongly support its structure. The combination of these distinct absorptions provides a definitive spectral fingerprint for benzophenone.<\/p>\n\n\n\n

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

Transmitance 1.0 Benzophenone Infrared Spectrum 0.8 0.6 0.4 0.2 0.0 3500 3000 2500 2000 1500 1000 500 Wavenumbers (cm-1) The Correct Answer and Explanation is: Correct Answer: This is the infrared (IR) spectrum of benzophenone. Explanation: The provided image displays the infrared spectrum for benzophenone, a diaryl ketone. The key absorption bands in the spectrum directly […]<\/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-258944","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/258944","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=258944"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/258944\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=258944"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=258944"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=258944"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}