chemistry

CHEMICAL BOND

  

1.

Valency of an element indicates

1)

Combining capacity with hydrogen

2)

Acidity

3)

Number of valence electrons

4)

None

2.

Between Atoms of a molecule there exists

1) Only attractive forces

2) Only repulsive forces

3) Both attractive and repulsive forces

4) Neither attractive nor repulsive forc

s

3.

When two atoms of chlorine combine to form one molecule of chlorine gas,

the energy of the molecule is

1)

Greater than that of separate atoms

2)

Equal to that of

ep r te atoms

3)

Lo  er than that of separate atoms

.

4)

None of these

4.

Most energetic species among the following is

1)

H

2) Ne

3) F

4) F

5.

During, bond formation potential energy of the system

1.

Increases  2. Decreases   3. Remains the same

4.Cannot be predicted

6.

HH   H2     this is an example for

1.

Endothermic reaction

2. Exothermic reaction

3.

Either exothermic or endothermic

4. Neither exothermic nor endothermic

7.

Duplet configuration is not found in

1.

Hydride ion

2. Hydrogen molecule

3.

Lithium cation

4. Be3+

8.

In a short period as the atomic number increases, the valen y of elements

with respect to Hydrogen

1. Decreases

2. Rema ns c nstant

3. First increases and then decreases

4. Incre ses

9. The element showing highest valency with respe t to oxygen is

1. Sodium

2. Aluminium

3. Chlorine

4. Sulphur

10.The number of valency electrons and the valency with respect to hydrogen are equal for

	1.	Sulphur		2.	Silicon
	3.	Phosphorus		4.	Chlorine