Question

Study the extract of the periodic table given below and answer the questions that follow. Give the alphabet corresponding to the elements in the question. DO NOT repeat an element .

A

C

D

E

B

G

F

1. Which element forms electrovalent compound with G?
2. The ion of which element will migrate towards the cathode during electrolysis?
3. Which non metallic element has the valency of 2?
4. Which is an inert gas?

Answer 1

1. Correct answer B .

An electrovalent bond is a chemical bond formed by the transfer of electrons. In an Electrovalent bond, ions are held together by the electrostatic force of attraction between the oppositely charged ions. An electrovalent bond is also called an ionic bond. G is present in group 17 and period 3. The element will be Chlorine (Cl). B is present in period 3 and group 2. So B will be Magnesium (Mg).

Mg - 2,8,2

Cl- 2,8,7

Two electrons of Mg will be transferred to a 2 Cl atom.

$$\begin{gathered} Mg\to M{g}^{2+}+2e^{-} \\ 2Cl+2e^{-}\to 2C{l}^{-} \end{gathered}$$

Then $Mg+C{l}_2\to MgC{l}_2$

ii. B.

B is present in group 2 and period 3 . B will be Magnesium (Mg). Group 2 elements are electropositive elements. They have a tendency to remove electrons from their valence shell and form cations. Generally, cations are move towards the cathode during electrolysis. Because the cathode is a negatively charged electrode. So cations move towards the cathode.

iii. E

E is present in group 16 and period 2. Elements present in the right side of the periodic table show non-metallic character Valence electron present in group 16 elements is 6. They have a tendency to attract 2 electrons to attain stability. So valency is 2.

iv) Inert gas is F

F is present in group 18. group 18 elements are called inert gas or Noble gas elements. Because valence electrons present is 8. They are highly stable.