Hi your guess is perfect!
Starting compound is saturated cyclic alcohol, it doesn't posses sp2 bonds.
Alcohol characteristic bands are O-H stretch which is very broad and strong & C-O stretch which is also strong.
O-H stretch is in the region 3200 3600 cm-1 & C-O stretch is in the region 1050-1150 cm-1, these two peaks are absent in product alkene. Moreover product alkene show =C-H stretch in the region 3010-3100 cm-1 and C=C stretch region 1620-1680 cm-1 & a strong band in the region 675-1000 cm-1 due to =C-H bending, these are absent in reactant alcohol.
Hope this helped you!
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