• Chemistry - Section 1
66. 

Equal masses of oxygen, hydrogen and methane are kept under identical conditions. The ratio of the volumes of gases will be

A. 2 : 16 : 2
B.

2 : 16 : 1

C.

1 : 16 : 2

D.

1 : 1 : 1


67. 

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

A. 1.8 gram of H2O
B.

12 moles of KMnO4

C.

0.6N H2SO4

D.

4.6 gram of C2H5OH


68. 

The mass number of an atom is equal to

A. the number of protons
B.

प्रोटॉन और इलेक्ट्रॉनों की संख्या

C.

न्यूक्लियंस की संख्या

D.

न्यूट्रॉन की संख्या


69. 

The maximum number of covalent formed by nitrogen is

A. 1
B.

2

C.

3

D.

4


70. 

The formula C6H5-CO-CH3 represents

A. Acetone
B.

सिरका अम्ल

C.

असितोफेनोने 

D.

फेनील एसीटेट