The tendency to form monovalent compounds among the Group $13$ elements is correctly exhibited in:

The $P-P-P$ bond angle in white phosphorus is

In which of the following reactions are the products not correctly matched?

Choose the correct statements about the hydrides of group $15$ elements.
$A$. The stability of the hydrides decreases in the order $NH_3 > PH_3 > AsH_3 > SbH_3 > BiH_3$
$B$. The reducing ability of the hydrides increases in the order $NH_3 < PH_3 < AsH_3 < SbH_3 < BiH_3$
$C$. Among the hydrides,$NH_3$ is strong reducing agent while $BiH_3$ is mild reducing agent.
$D$. The basicity of the hydrides increases in the order $NH_3 < PH_3 < AsH_3 < SbH_3 < BiH_3$
Choose the most appropriate from the option given below:

$A$ mixture of ammonia and air at about $800\,^{\circ}C$ in the presence of $Pt$ gauze forms:

Which of the following is $NOT$ a property of red phosphorus?