II-A|| II-B group||IIIrd group Cations

Which one is correct group reagent for group cations?

._(90)Th^(232) belongs to III group. It items an alpha -particle. The daughter element belongs to a. I group b. II group III. Group d. IV group

Why Na_(2)S cannot be used in place of H_(2)S (in presence of HCl ) as a reagent for II^(nd) group cations ?

Out of 1000 students 658 failed in the agregate,166 in the aggregate and in group- 1434 in aggregate and in group-II,372 in group-I Find out how many failed in all the three.te and in group-II,372 in group-I,590 in group-II and 126 in both the groups.