Question

valency of an element A is 3 and that of element B is 2 . write the formula of a compound formed by combination of A and B

Answer 1

The cation is A3+ nd anion is B2-
so the compund is
2A3+ + 3B2- ------> A2B3.
Hope it helps :)

Answer 2

Explanation:

The valency of element A is 3, that is, oxidation state of element A is $A^{3+}$. The valency of element B is 2, that is, oxidation state of element B is $B^{2-}$.

This means that 2 atoms of A reacts with 3 atoms of B.

Therefore, the reaction will be as follows.

      2$A^{3+} + 3B^{2-} \rightarrow A_{2}B_{3}$