Question

If the chemical formula of metal carbonate is $ {{M}_{2}}C{{O}_{3}} $ , then choose the correct option from the following
1. The chemical formula of metal iodide will be $ MI $
2. The chemical formula of metal nitride will be $ {{M}_{3}}{N}_{2} $
3. The chemical formula of metal phosphate will be $ {{M}_{3}}P{{O}_{4}} $
(A) $ 1 $ and $ 2 $ only
(B) $ 2 $ and $ 3 $ only
(C) $ 1 $ and $ 3 $ only
(D) Only $ 2 $

Answer 1

Hint :The chemical formula of metal carbonate is $ {{M}_{2}}C{{O}_{3}} $ . The valency of Metal in $ {{M}_{2}}C{{O}_{3}} $ is $ +1 $ . By identifying the valency of each element, crossing over the valency with the elements, we can calculate the chemical formula.

Complete Step By Step Answer:
For Metal Iodide, the valency of M is $ +1 $ and valency of Iodide is $ -1 $
By crossing over, we will get MI
crossing over: M( $ -1 $ ) I( $ +1 $ ) $ M(-3),P{{O}_{4}}(+1) $ $ =MI $
The chemical formula of Metal iodide is MI
Therefore, the first statement: The chemical formula of metal iodide will be $ MI $ is correct
For Metal nitride, the valency of M is $ +1 $ and Nitride is $ -3 $
By crossing over, we will get $ {{M}_{3}}N $
crossing over: $ M(-3), $ $ N(+1) $ $ ={{M}_{3}}N $
The chemical formula of Metal nitride is $ {{M}_{3}}N $
Therefore, the second statement : The chemical formula of metal nitride will be $ M_3N_2 $ is incorrect
For Metal Phosphate, the valency of M is $ +1 $ and Phosphate is $ -3 $
By crossing over, we will get $ {{M}_{3}}P{{O}_{4}} $
crossing over: $ M(-3),P{{O}_{4}}(+1) $
The chemical formula of Metal phosphate is $ {{M}_{3}}P{{O}_{4}} $
Therefore, the last statement: The chemical formula of metal phosphate will be $ {{M}_{3}}P{{O}_{4}} $ is correct
Thereby the correct option is C
The option a) $ 1 $ and $ 2 $ only is incorrect
The option b) $ 2 $ and $ 3 $ only is incorrect
The option d) Only $ 2 $ is incorrect
Metal carbonate belongs to a type of base which has the ability to produce the required salt , water and carbon dioxide when they are forced to react with acid.
The option (C) $ 1 $ and $ 3 $ only is correct.

Note :
The chemical formula of Metal iodide is MI. The chemical formula of Metal nitride is $ {{M}_{3}}N $ . The chemical formula of Metal phosphate is $ {{M}_{3}}P{{O}_{4}} $ . .In these types of questions eliminate the incorrect option to make the question simpler.