One Mark Questions Answers

CHEMICAL BONDING

TEXT BOOK EXERCISES

I. Choose the correct answer :

1. Number of valence electrons in carbon is

(a) 2

(b) 4

(c) 3

(d) 5

[Answer: (b) 4 ]

2. Sodium having atomic number 11, is ready to _――― electron / electrons to attain the nearest noble gas electronic configuration.

(a) gain one

(b) gain two

(c) lose one

(d) lose two

[Answer: (c) lose one]

3. The element that would form anion by gaining electrons in a chemical reaction is _{――― .}

(a) potassium

(b) calcium

(c) fluorine

(d) iron

[Answer: (c) fluorine]

4. Bond formed between a metal and non metal atom is usually _――― .

(a) ionic bond

(b) covalent bond

(c) co-ordinate bond

[Answer: (a) ionic bond]

5. _――― compounds have high melting and boiling points.

 (a) Covalent

(b) Coordinate

(c) Ionic

[Answer: (c) Ionic]

6. Covalent bond is formed by _――― .

(a) transfer of electrons

(b) sharing of electrons

(c) sharing a pair of electrons

[Answer: (b) sharing of electrons]

7. Oxidising agents are also called as _――― because they remove electrons form other substances.

(a) electron donors

(b) electron acceptors

[Answer: (b) electron acceptors]

8. Elements with stable electronic configurations have eight electrons in their valence shell. They are _――― .

(a) halogens

(b) metals

(c) noble gases

(d) non metals

[Answer: (c) noble gases]