Chemistry MCQs

Question 1

Concentration of a material which is lethal to 50% animal is called

Accepted Answer

LD 50

Answer

LC 50

Answer

NOAEL

Answer

ADI

Question 2

The weight of 6.023 × 10 23 atoms of carbon is

Accepted Answer

12 gms

Answer

120 gms

Answer

1.2 gms

Answer

0.12 gms

Question 3

When a lead storage battery is discharged,

Accepted Answer

Sulphuric acid is consumed

Answer

SO 2 is evolved

Answer

Lead sulphate is consumed

Answer

Lead is formed

Question 4

Air shows the property of

Accepted Answer

Both A and B

Answer

N 2

Answer

O 2

Answer

None of these

Question 5

The number of atoms present in 21.6 gram of silver (atomic weight = 108) are same as the molecules in

Accepted Answer

12 moles of KMnO 4

Answer

1.8 gram of H 2 O

Answer

0.6N H 2 SO 4

Answer

4.6 gram of C 2 H 5 OH

Question 6

Which one is a soluble salt in H 2 O?

Accepted Answer

CaCl 2

Answer

CuS

Answer

Zn(OH) 2

Answer

PbCl 2

Question 7

Which is not a green house gas ?

Accepted Answer

N 2 O

Answer

CO 2

Answer

CH 4

Answer

Chlorofluorocarbons

Question 8

Oxygen has (+) oxidation number only in

Accepted Answer

OF 2

Answer

C 12 O

Answer

H 2 O (2)

Answer

N 2 O

Question 9

Which of the following causes the rusting of iron? a. Oxidation b. Reduction c. Chemical reaction with oxygen d. Chemical reaction with CO 2

Accepted Answer

A and C

Answer

A and B

Answer

B and C

Answer

C and D