Give the general variation of electron gain enthalpies in the periodic table.

The highest electronegativity in the periodic table is of:

Halogens have maximum negative electron gain enthalpy in the respective periods of the periodic table. Why ?

The second electron gain enthalpy of oxygen is

Why Noble gases have zero electron gain enthalpy?

The familyof elements having highest ionisation enthalpy in the periodic table is

The number of elements in the fifth period of periodic table is

What do you mean by the term electron gain enthalpy? How does electron gain enthalpy change along a period and in a group?

How does the tendency of the elements to lose electrons change in the Modern Periodic Table in (i) a group, (ii) a period and why?

Give the number of elements in 2^(nd)and5^(th) period in Modern Periodic Table.