Answer: The chemical formula for ammonia is

Step-by-step explanation:
Ammonia is the common name for nitrogen trihydride. It is formed by the combination of two elements which are nitrogen and hydrogen.
Nitrogen is the 7th element of the periodic table. The electronic configuration of this element is

This element requires 3 electrons to attain stable electronic configuration.
Hydrogen is the 1st element of the periodic table. The electronic configuration of this element is

This element requires 1 electron to attain stable electronic configuration.
Thus, 3 atoms of hydrogen will bond with 1 atom os hydrogen to form a chemical compound of

Hence, the chemical formula for ammonia is
