Question

Find the following information for the elements shown in Fig.:

1. Name of the element
2. Symbol
3. Total number of electrons
4. Number of valence electrons
5. Valency of the element
6. Number of protons
7. Atomic number

Answer 1

The electron configurations of the elements shown in Fig. are:

1. Sodium: 2, 8, 1
2. Chlorine: 2, 8, 7
3. Argon: 2, 8, 8
4. Calcium: 2, 8, 8, 2

The required information is given below:

Information	(a) Sodium	(b) Chlorine	(c) Argon	(d) Calcium
(i) Name of the element	Sodium	Chlorine	Argon	Calcium
(ii) Symbol	Na	Cl	Ar	Ca
(iii) Total number of electrons	11	17	18	20
(iv) Number of valence electrons	1	7	8	2
(v) Valency of the element	1	1	0	2
(vi) Number of protons	11	17	18	20
(vii) Atomic number	11	17	18	20

Explanation:

In a neutral atom, the number of protons equals the number of electrons. The atomic number is equal to the number of protons. Valency depends on the number of electrons in the outermost shell.