Question

Identify the correct set of electrovalent compounds from the following in which the metal has electrovalence 2 and non-metal has electrovalence of 3.
(A) Calcium sulphide
(B) Barium nitride
(C) Magnesium phosphide
(D) Aluminium nitride
(E) Magnesium fluoride
A. B & C
B. B & D
C. C & D
D. A, B, C & E

Answer 1

Electrovalent compounds are nothing but the ionic compounds. In ionic compounds the electrons transfer from metal to nonmetals. The ionic bond is going to form between a metal and a nonmetal.

Complete step by step answer:
- In the question it is given to find the correct set of electrovalent compounds from the following in which the metal has electrovalence 2 and non-metal has electrovalence of 3.
- To know about the valence of the metal and non-metal in the given compounds first we should know the molecular formula of the given compounds.
- The molecular formula of the given compound A Calcium sulphide is CaS.
- The valence of the calcium ion in calcium sulphide is +2 and the valency of sulphide ion is -2.
- The molecular formula of the given compound B Barium nitride is $B{{a}_{3}}{{N}_{2}}$ .
- The valence of the barium ion is +2 and the valence of the nitrogen nitride ion is -3.
- The molecular formula of given compound C Magnesium phosphide is $M{{g}_{3}}{{P}_{2}}$ .
- The valence of the magnesium ion is +2 and the valence of the phosphide ion is -3.
- The molecular formula of the given compound D Aluminium nitride is AlN.
- The valence of the aluminum ion is +3 and the valence of the nitride ion is -3.
- The molecular formula of the given compound E Magnesium fluoride is $Mg{{F}_{2}}$ .
- The valence of the magnesium is +2 and the valence of the fluoride is -1.
- By seeing all the valence of the metals and non-metals in the given compounds we can easily say that the compounds B and compound C showing the metal has electrovalence 2 and non-metal has electrovalence of 3.
- Therefore compound B and compound C are showing the required valences as per the given question.

- So, the correct option is A.

Note: Electrovalence of the metal means the number electrons lost by the metal and electrovalence of the non-metal means the number electrons gained by the non-metal from the metal in the given ionic compound.