Question

Compute the differences in the masses of 1 mole of aluminiumatomand 1 mole of aluminium ion (mass of electron = 9.1*10^-28g).Which one is heavier ?

Answer 1

Aluminum atom: Al

Aluminum ion : Al³⁺.

Atomic number of Al is 13 and atomic number is 27. This means that there are 13 electrons, 13 protons and 14 neutrons present in aluminum atom.

While in aluminum ion, the number of neutron and proton is same but it contains 3 less electrons than Al atom.

So the mass of Al ion should be lesser than the mass of Al atom.

Difference in the mass of 1 mole Al atom and 1 mole Al ion = mass of 3 mole electrons = 3 x 9.1x 10^-28 x 6.023 x10²³ g