Question

Define atomic and mass number of an element

Answer 1

All the atoms of a particular element have the same atomic number (number of protons). The atoms of different elements have different numbers of protons. For example, all oxygen atoms have 8 protons and all sodium atoms have 11 protons. The mass number of an atom is the total number of protons and neutrons it contains.

Answer 2

Atomic Number of an element= No. of protons present in it.

Mass Number of an element= No. of protons+No. of Neutrons present in it.

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