Answer:
The molecular formula of the compound :
Explanation:
The empirical formula of the compound =
The molecular formula of the compound =
The equation used to calculate the valency is :

We are given:
Mass of molecular formula = 86 g/mol
Mass of empirical formula = 43 g/mol
Putting values in above equation, we get:

The molecular formula of the compound :

The first reaction is a synthesis reaction (A+B -> AB)
The answer is A! Hoped it’s sure!
Explanation: A chemical reaction involves breaking bonds in the reactants, rearranging the atoms into new groupings (the products), and forming new bonds in the products.
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