Question

Given the atomic number, the number of electrons and number of neutrons as 1, 2, and 0 respectively for an ion. Find the mass number, number of protons, charge, and symbol of the ion.

Answer 1

• As the number of protons is given as one, the atomic number is also one and thus the element is hydrogen (H).
• Number of electrons of a neutral hydrogen atom will be 1. Here the number of electrons is given as 2, so we can understand that the hydrogen atom has gained one electron. Thus it will have a charge of -1.
• Since the charge on hydrogen is -1, the symbol will be: H^-1
• Mass number = number of protons + number of neutrons = (1+0) = 1.
• Hence the symbol: H^-1, number of protons = 1, mass number = 2, charge= -1.