Mass number is the

(a)

Number of protons

(b)

Sum of protons and electrons

(c)

Number of neutrons

(d)

Sum of protons and neutrons

Which of the following statement regarding an atom is always correct?

(a)

An atom has equal number of electrons and protons

(b)

An atom has equal number of electrons and neutrons

(c)

An atom has equal number of electrons, protons and neutrons

(d)

An atom has equal number of protons and neutrons

Atomicity of Chlorine and Neon is

(a)

Mono atomic and mono atomic

(b)

Mono atomic and diatomic

(c)

Diatomic and diatomic

(d)

Diatomic and mono atomic

Mass of an electron is

(a)

9.1083 x 10^-31kg

(b)

9.1083 x 10^-24kg

(c)

1.67262 x 10^-27kg

(d)

1.67 x 10^-24gm

Which of the following pairs are isotopes?

(a)

Oxygen and ozone

(b)

Ice and water

(c)

NO and NO₂

(d)

Hydrogen and deuterium