C₅H₁₀O

From the molecular formula, the compound has "1 degrees of unsaturation" (one double bond, carbonyl or ring).

3400 cm-1:	no OH or NH present		3100 cm-1:	no peak to suggest sp2 CH
2900 cm-1:	strong peak indicating sp3 CH		2200 cm-1:	no unsymmetrical triple bonds
1710 cm-1:	strong carbonyl absorbance		1610 cm-1:	no peak to suggest C=C

The spectrum seems to be consistent with a simple aliphatic carbonyl compound.

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Structure:

IUPAC Name: 3-pentanone (diethyl ketone)