Elena makes the table below to determine the number of atoms of each element in the chemical formula 3(nh4)2so4. what mistake did elena make?

Atoms are the smallest particles of an element that can take part in a chemical reaction. The compound 3(NH4)SO4 has. 3 nitrogen atoms, 12 hydrogen atoms, 1 sulfur atom and 4 oxygen atoms. To get atoms of nitrogen we multiply 1 by 3 outside the brackets to get 3, for hydrogen atoms, inside the brackets we have 4 atoms then we multiply by 3 to get 12. Sulfur atom is only one since there is no brackets or subscript encompassing it, for oxygen, there are 4 atoms as a result of multiplying one by the subscript 4.
Therefore, she should not have multiplied the sulfur atoms by the subscript 4

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