An atom of sodium-23 (atomic number = 11) has a positive charge of + 1. Given this information, how many

electrons does it have? How many protons and neutrons does this atom have?

Proton number is the same as atomic number = 11

as electrons have a mass which is so small its counted as 0 and protons and neutrons relative mass is 1

the number of neutrons = 23 - 11 = 12 neutrons

In a neutral atom the number of electrons = number of protons but here we have a + 1 ion so there is one less electron then proton therefore the number of electrons = 10