(a) What is meant by 'atomic number of an element'?

(b) Complete the table given below:

	No of protons	No of electrons	No of neutrons	Atomic number	Mass number
3517Cl
3717Cl

(c) Write down the electronic configuration of

(i) Chlorine atom

(ii) Chloride ion

(a) Atomic number of an element is the number of:

• electrons present in its neutral atom.
• protons present in the nucleus of its atom.
• positive charge in the nucleus of its atom.
• it is denoted by Z.

(b) Complete the table given below:

(c) Write down the electronic configuration of

(i) Chlorine atom — 2, 8, 7

(ii) Chloride ion — 2, 8, 8