Which of the following compounds is used as a refrigerant?

Which of the following oxides will not act as a reducing agent?

The strongest reducing agent among the following is:

Explain the nature of hydride compounds of group-$15$ elements. Explain the nature of oxide compounds of group-$15$ elements. Write a note on halide compounds of group-$15$ elements.

$A + H_2O \to B + HCl$
$B + H_2O \to C + HCl$
Compound $(A), (B)$ and $(C)$ will be respectively

In the nitrogen family,the $H-M-H$ bond angle in the hydrides $MH_3$ gradually becomes closer to $90^o$ on going from $N$ to $Sb$. This shows that gradually: