N_(0)//2 atoms of X_((g)) are converted into X_((g))^(o+) by energy E_(1), N_(0)//2 atoms of X_((g)) are converted inot X_((g))^(ɵ) by energy E_(2). Hence ionisation potential and electron affinity of X_((g)) per atom are

N_(0)//2 atoms of X_((g)) are converted into X_((g))^(o+) by energy E_

1.	N_(0)//2 atoms of X_((g)) are converted into X_((g))^(o+) by energy E_(1), N_(0)//2 atoms of X_((g)) are converted inot X_((g))^(ɵ) by energy E_(2). Hence ionisation potential and electron affinity of X_((g)) per atom are
Answer» `(2E_(1))/(N_(0)),(2(E_(2)-E_(1)))/(N_(0))` `(2E_(1))/(N_(0)), (2E_(2))/(N_(0))` `((E_(1)-E_(2)))/(N_(0)), (2E_(2))/(N_(0))` None is correct. Solution :Let the ionisation energy of `X_((G)) = IE` per ATOM and electron affinity of `X_((g)) = -EA` per atom. `X_((g)) rarr X_((g))^(o+) + e^(-)` Energy required to ionise `(N_(0))/(2)` atoms of `X_((g)) = (N_(0))/(2) xx IE = E_(1)` (given) `:. IE = (2E_(1))/(N_(0))` `X_((g)) rarr X_((g))^(o+) ("Energy" = (N_(0))/(2) xx IE)`...(iii) `X_((g)) + e^(-) rarr X_((g))^(ɵ)[["Energy RELEASED to"],["add electrons to" (N_(0))/(2)],["atoms of"X_((g)) = -(N_(0))/(2) xx EA]]`...(iv) Energy for the process `X_((g))` to `X_((g))^(ɵ) = E_(2)` (given). Therefore, adding Eq. (iii) and (iv), we give `((N_(0))/(2) xx IE - (N_(0))/(2) xx EA) = E_(2)` (given)...(v) SUBSTITUTE the value of `IE` from Eq. (ii) in Eq. (v). `(CANCEL(N_(0))/(cancel(2)) xx (cancel(2)E_(1))/(cancel(N_(0))) -(N_(0))/(2) xx EA) = E_(2)` `-(N_(0))/(2) xx EA = E_(2) - E_(1)` `:. -EA = (2(E_(2)-E_(1)))/(N_(0))` `:. IE = (2E_(1))/(N_(0))"atom"^(-1)` and `-EA = (2(E_(2)-E_(1)))/(N_(0))`