write the electronic configurations of the following ions : `(a) H^(-) (b) Na^(+) (c) O^(2-), (d) F^(-)`
(ii) write are the atomic numbers of elements whose outermost electrons are respersented by `(a) 3s^(1) (b) 2p^(3) and (c) 3p^(5) ? `
(iii) which atoms are indicated by the following configurations ?
`[He]2s^(1) (b) [Ne] 3s^(2) 3p^(3) (c). [Ar] 4s^(2) 3d^(1)` .

Explanation

i. a. `H^(Θ)=1s^(2)`
b. `Na^(o+)=1s^(2)2s^(2)2p^(6)`
c. `O^(2-)=1s^(2)2s^(2)2p^(6)`
d. `F^(Θ)=1s^(2)2s^(2)2p^(6)`
ii. a. `3s^(1)=11(1s^(2)2s^(2)2p^(6)3s^(1))`
b. `2p^(3)=7(1s^(2)2s^(2)2p^(3))`
c. `3d^(6)=26(1s^(2)2s^(2)2p^(6)3s^(2)3p^(6)3d^(6)4s^(2))`
iii. a. `[He]2s^(1)=Li` (atomic number `2+1=3)`
b. `[Ne]3s^(2)3p^(3)=P` (atomic number `=10+2+3=15)`
c. `[Ar]4s^(2)3d^(1)= Sc` (atomic number `=18+2+1=21)`