chem51LB_lab5_IR.doc

chem51LB_lab5_IR.doc - group. The big peak at 3300cm-1 is...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
Infrared spectroscopy is used to identify unknown compounds. The infrared light is used to activate vibrations in bonds when they are stretched out. These vibrations of different frequencies are then plotted on a graph. Since each compound has components that vibrate at different frequencies, each component has a unique compiled plot. By analyzing the peaks in each plot, the structure and indentity of each compound can be determined. Unknown compound 18 has a peak at -1713.2cm -1 , which is characteristic of a carbonyl group, which is closely related to a carbonyl acid. Another peak at 2675.6cm -1 confirms the presence of an OH group on the carboxylic acid. A peak at 2928.6cm -1 is indicative of a sp 3 hybridized C-H bond. Unknown 57 has a peak at ~1650cm -1 that is characteristic of a C=O bond, hence a carbonyl
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: group. The big peak at 3300cm-1 is the most indicative, showing the presence of a N-H group. Unknown 23 shows the presence of a monosubstituted aromatic ring with a series of small peakes from ~1900-1600cm-1 and the peak at 1925.9cm-1 indicates that the ring has double bonds. The peak at 3414.2cm-1 shows the presensce of a N-H bond while spikes from 2813.6cm-1 to 3051.1cm-1 show the presence of sp2 and sp3 C-H stretches, showing the presence of a methyl groups. Our group unknown, number 14, shows the small peaks characteristic of a monosubstituted ring ring structure between 1941.7 and 2232.3 cm-1 and a very characteristic series of small peaks that for an almost smooth curve are present at 3370.1 cm-1 . This is indicative of an OH group being present. Post Lab: 1) 2) 3) 4) 1a....
View Full Document

This note was uploaded on 07/08/2009 for the course CHEM 40639 taught by Professor Yixuan during the Spring '09 term at UC Irvine.

Ask a homework question - tutors are online