ATOMIC AND IONIC RADII -The atomic and ionic radii of group 15 elements are lower than the atomic radii of the corresponding group 14 elements. As we go down the group, the atomic radii increase with increase in atomic number..


The first ionisation enthalpies of the group fifteen elements are higher than the corresponding members of the group fourteen elements. As we go down the group, the ionisation enthalpies decrease.


The electronegativity values of elements of group fifteen are higher than the corresponding elements of group fourteen. As we go go down the group, the electronegativity value decreases.


The elements of group fifteen are less metallic.


The melting points of group fifteen elements first increase from nitrogen to arsenic and then decrease to antimony and bismuth.


The elements of group fifteen also show a tendency to form bonds with itself (self linking of atoms ) known as catenation


Why are pentahalides more covalent than trihalides

In pentahalides, the oxidation state is more (+5)than in trihalides (+3).

Why is BiH3 the strongest reducing agent amongst all the hydride of group 15

Among the hydrides of group 15, BiH3 is least stable because Bi has largest size in the group and has least tendency to form covalent bond with small hydrogen atom.

Why is N2 less reactive at room temperature

Due to the presence of a triple bond, it has very high bond dissociation energy (941.4kJ per mol) and therefore it does not react with other elements under normal conditions and is very unrealized.

What is the covalence of nitrogen in N2O5

The covalence of nitrogen is four because it has four shared pair of electrons.

Bond angle in PH3+ is higher than in PH3+ WhyIn PH4+ all the four orbitals are bonded, whereas in PH3+ there is a lone pair of electrons on P.

What happens when PCl5 is heated

On heating, PCl5 first sublimes and then decomposes on strong heating: PC5———–PCl3+Cl2

Write a balanced equation for the hydrolytic reaction of PCl5 with heavy water.

PCl5 +D2O————–POCl3 +2DCl

What is the basicity of H3PO4

The basicity of H3PO4 is three.

What happens when H3PO3 is heated

On heating, H3PO3 disproportionates to give orthophosphoric acid and phosphate.

4H3PO3———– 3H3PO4 + PH3

ortho phosphoric acid phosphine

Why is H2O a liquid and H2S a gas

Due to high elecronegativity of oxygen and its small size, there are strong hydrogen bonding in water. As a result, the molecules exists as associated and is liquid at room temperature. But there is negligible hydrogen bonding in H2S because of low elecronegativity of S.

Which of the following does not react with oxygen directly Zn,Ti,Pt,Fe

Pt; because it is a noble metal.