Correct statements from the following are:

A. Nitrogen in oxidation states from +1 to +4 disproportionates in acid medium.

B. Nitrogen has the ability to form $\mathrm{d} \pi$ - $\mathrm{p} \pi$ multiple bonds with itself and other elements with small size and high electronegativity.

C. N-N single bond is stronger than P-P single bond.

D. Nitrogen has highest density in its group due to small size.

E. The maximum covalency of nitrogen is four since it has only four valence orbitals for bonding.

Choose the correct answer from the options given below:

The electronegativity of a group 13 element ' E ' is same as that of Ge (on Pauling scale and upto one decimal point). The CORRECT statements about $\mathrm{E}^{3+}$ are

A. It can act as a reducing agent.

B. It can act as an oxidizing agent.

C. $\mathrm{E}^{3+}$ is more stable than $\mathrm{E}^{+}$.

D. The standard electrode potential value for $\mathrm{E}^{3+} / \mathrm{E}$ is positive.

Choose the correct answer from the options given below :

A monoatomic anion (A ) has 45 neutrons and 36 electrons. Atomic mass, group in the periodic table and physical state at room temperature of the element (A) respectively are

Given below are two statements :

Statement I : The covalency of oxygen is generally two but it can exceed upto four. The oxidation state of oxygen in $\mathrm{SO}_2$ is -2 and in $\mathrm{OF}_2$ it is +2 .

Statement II : The anomalous behaviour of oxygen when compared to the other elements of group 16 is due to its small size and high electronegativity.

In the light of the above statements, choose the correct answer from the options given below