Question

An atom of aluminium has 13 protons & 14 neutrons : the mass number of aluminum is _____________(a)13 (b) 27 (c) 14 (d) 72​

Answer 1

Answer:

Explanation:

Name Aluminum

Atomic Mass 26.982 atomic mass units

Number of Protons 13

Number of Neutrons 14

Number of Electrons 13

Answer 2

Answer:

Mass number of an atom is the sum of numbers of protons and neutrons. This is because the mass of electrons is much smaller then neutrons and protons, so we don't count them in. Answer is 13+14=27.