There are 16 atoms in 4NH3
The smallest part of the matter is called atom .
An atom contains neutron, proton and electrons.
In the given question there is one molecule of NH3 , there is one Nitrogen atom and three hydrogen atom . So, for four molecule of NH3 there are four nitrogen atom and 4*3 hydrogen atom means twelve hydrogen atom.
So, total number of atoms in 4NH3 is 4+12 = 16
To learn about an atom here
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