The chemical formula for the phosphorus molecule is:

What happens when $PCl_{5}$ is heated?

Of the following,the most acidic is

Which of the following elements does not form stable diatomic molecules?

When $NH_3$ reacts with $Cl_2$,which of the following statements are correct?
$(a)$ $NCl_3$ is formed when $Cl_2$ is in excess.
$(b)$ $N_2$ is formed when $Cl_2$ is in excess.
$(c)$ $N_2$ is formed when $NH_3$ is in excess.
$(d)$ $NCl_3$ is formed when $NH_3$ is in excess.

Which of the following statements is $NOT$ correct?