Periodic Properties

Q. What happens with metallic character in group & period of periodic table?

Metallic character decreases, as we go to the right side in a period and increases when we move downwards in a group.

Q. why is periodic properties independent of atomic mass?

atomic masses are calculated values for naturally occuring elements, so it is independent of periodic properties

Q. what are transition metals and inner transition metals ? In which group and block do they come?

Many scientists describe a "transition metal" as any element in the d-block of the periodic table, which includes groups 3 to 12 on the periodic table. In actual practice, the f-block lanthanide and actinide series are also considered transition metals and are called "inner transition metals".
The main difference between transition metals and inner transition metals is that transition metal atoms have their valence electrons in the outermost d orbital whereas inner transition metal atoms have their valence electrons in the f orbital of the inner penultimate electron shell.

Q. Please explain order of chlorine isobars?

Both Chlorine-35 & Chlorine-37 will have same atomic as well as ionic radii.
becuase they differ in no of neutrons which has no charge hence there will be no effect of 2 less neutrons on Zeff
in both the electron and protons are equal

Q. The halogen that most easily reduced is?

Fluorine being most electronegative atom, has a high tendency to gain electron. Thus, it readily forms anions.