Question

Give the structure that corresponds to the following molecular formula and 1H NMR spectrum: C4H10O2: ? 1.36 (3H, d, J = 5.5 Hz); ? 3.32 (6H, s); ? 4.63 (1H, q, J = 5.5 Hz)

Answer 1

Δ 1.36 (3H, d, J = 5.5 Hz) 
CH*3-CH(X)(Y) 

δ 4.63 (1H, q, J = 5.5 Hz) 
CH3-CH*(X)(Y) 

Note: X anY can't have hydrogen attached, so they are probably O. 

δ 3.32 (6H, s); δ 4.63 (1H, q, J = 5.5 Hz) 
There is only C2H6O2 remaining, so this must be two CH3 groups; the attachment must be as an ether, and there must be two of them: 
CH3-CH(OCH*3)2