Give reason for the following:
Electron gain enthalpy of noble gas is almost zero.

Give the reason for the following: The first ionisation enthalpy of oxygen is smaller compared to nitrogen.

Account for the following: Electronic gain enthalphy of F is less negative than that of Cl

Second electron gain enthalpy Is ͟ ͟ ͟͟͟

Assign reason for the following:- The negative Value of electron gain enthalpy of fluorine is less than that of CI.

Justify the following: The electron gain enthalpy of 'F' is lower than that of 'Cl .

Give reason for the following. Sky in the moon appears dark.

Give reasons for the following:- i. elemental phosphorus does not exist as P_2 molecule ii. Noble gases are known as Inert gases.

Give reasons for the following: CO_2 is a gas whereas SiO_2 is a solid.

Give reason for the following:- HF is liquid but HCI is gas.