Does the ionisation enthalpy decreases along a group ? Give reasion

The first ionisation enthalpy is the least in

Assertion: On moving down the group, ionization enthalpy decreases. Reason: With decrease in size of the atom, the force of attraction between the nucleus and valence electrons decreases.

Explain the general periodic trend of first ionization enthalpy along a period and group in the periodic table.

Generally electron gain enthalpy increases along a period and decreases down the group. But electron gain enthalpy of oxygen is -141 kJ//mol while that of sulphur is -200 kJ//mol . Explain.

Analyse the following statements and correct them if there is a mistake. Down the group in .a periodic table ionisation energy decreases electronegativity increases.

What are the main factors due to which the ionisation enthalpy of the main group elements tends to decrease down a group ?

Say whether the following are true or false: a) On moving across a period ionization enthalpy decreases. b) Mg is bigger than Cl. c) Ionization enthalpy of Li is less than that of K.

The pronounced change from non-metallic to metallic behaviour and also increase in the basicity of oxides from nitrogen to bismuth in group 15 is principally due to increasing size of the atoms. The ionisation potential of nitrogen is very high on account of its small size. However, ionisation potential decreases regularly on descending the group. Which of the following fluorides does not exist?