Draw the atomic orbit structure diagram for formation of a -

(a) water molecule

(b) ammonia molecule

[at. no. H=1, O=8, N=7]

With the help of an atomic orbit structure diagram - explain the formation of :

(a) carbon tetrachloride

(b) methane

[at. no. : C=6, Cl=17, H=1]

Assertion: Noble gases have stable electronic configuration.

Reason: Atoms of elements other than noble gases have incomplete valence shell.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true and R is false.
4. A is false and R is true.

An element 'X' has same number of electrons in its first & in its outermost shell. The electronic configuration of X²⁺ is :

1. 2, 8, 1
2. 2, 8
3. 2, 8, 2
4. 2, 8, 8