Which one out of Na⁺ and Cl^- is bigger in size and why?

Out of P^3-,  S^2- and Cl^- ions, which has the smallest value of ionic radius and why?

Which one out of O and Se is bigger in size and why?

For each of the following pairs state which one has greater ionisation enthalpy:
(i) I, I^- (ii) Br, K.

Out of the following which has the smallest ionic 'Size and why: Li⁺, Na⁺, K⁺?

From amongst the following, choose the element with the lowest IE: Be, B and C.

What is the relationship between the first ionisation enthaplies and metallic properties?

What is the trend of ionisation enthalpy in a period?

What is the trend of ionisation enthalpy in a group?

Among the elements Li, K, Ca, S and Kr, which one has the highest first ionisation enthalpy and which one has the lowest first ionisation enthalpy?