The structure for the ammonium ion, NH4+ is shown above. How many protons and how many electrons.
The nitrogen atom, which has an atomic number of 7, contains 7 protons. The hydrogen atoms, which have an atomic number of 1, each contains 1 protons. In total there are 7 + 4(1) = 11 protons.
Nitrogen is a Group VA element and therefore contains 5 valence electrons and hydrogen is a Group IA element and therefore contains 1 valence electron:
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Together, the nitrogen and the four hydrogens have 5 + 4(1) = 9 valance electrons. Only 8 valence electrons are used to make NH4+, therefore, 1 electron has been lost from the structure in order to obey the octet rule. This gives the species a +1 charge.