Among the presented substances, Phosphoric acid - H₃PO₄ is the one made up of most atoms.
Atomicity refers to the number of atoms of each element in a compound. It is given by the corresponding subscripts.
We have 4 substances. To calculate the number of atoms in each one, we will sum the number of atoms that form them.
H + C + O = 2 + 1 + 3 = 6 atoms
H + N + O = 1 + 1 + 3 = 5 atoms
H + P + O = 3 + 1 + 4 = 8 atoms
H + S + O = 2 + 1 + 4 = 7 atoms
Among the presented substances, Phosphoric acid - H₃PO₄ is the one made up of most atoms.
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