If an atom has 7 protons, 8 neutrons and 4 electrons, what is the atom’s atomic symbol?

Answer 1

The number of protons determines which element it is; if you change the number of protons you'd be changing the element.

In this case, since you have an atom with 7 protons, the element you have is Nitrogen.

The mass number is the number of protons and neutrons, which would be 7 + 8 = 15 .

The charge is calculated by looking at the total number of protons (positive) and electrons (negative). Since you have 7 protons and 4 electrons, the total charge would be +7 -4 = +3.

Since mass number is the number to the top left and the atomic number is to the bottom left of the atomic symbol, you would have ¹⁵₇N³⁺ .