What happens in a single replacement reaction apex?

The more reactive element replaces lesser reactive one

Explanation:

Single replacement reaction is a chemical reaction in which more reactive element displaces the less reactive element from its salt solution.

A more reactive element is one which can easily lose or gain electrons as compared to the other element.

Example:

Here Zinc being more reactive than hydrogen can easily displace hydrogen from its salt solution and form zinc chloride and hydrogen in elemental form.

the maximum mass of nh3 is nh3 in grams