`H_(2)O_(2)` and heavy water was discovered by respectively :

Heavy water was discovered by Urey.

H_2O_2 and heavy water were discovered respectively by

H_(2) and O_(2) are kept in mass ratio 1:8 respectively at 6 atm. If small orifice is made then relative rate of effusion of H_(2) with respect to O_(2) initially is :

Heavy water ( D_2O) is :

18g of ice is converted into water at 0^(@)C and 1 atm. The entropies of H_(2)O (s) and H_(2)O (l) are 38.2 and 60J/mol K respectively. The enthalpy cange for this conversion is:

The oxidation number of sulphur in H_(2)SO_(4),H_(2)S_(2)O_(4) and H_(2)S_(2)O_(6) are respectively