Which pair consists of a molecular formula and its corresponding empirical formula?
(1) C2H2 and CH3CH3 (3) P4O10 and P2O5
(2) C6H6 and C2H2 (4) SO2 and SO3
(1) C2H2 and CH3CH3 (3) P4O10 and P2O5
(2) C6H6 and C2H2 (4) SO2 and SO3