Question

explain with example mass no.

Answer 1

All atoms are characterized by theiratomic numbers. (ii) Mass number isdefined as the sum of the total numberof protons and neutrons present in the nucleus of an atom. For example there are 6 protons and 6 neutrons in the nucleus of carbon, so its mass numberis 12.

Answer 2

Mass number of an atom is the sum of no. of protons and no. of neutrons present in the nucleus of the atom .Mass no. is also called as atomic no.
for eg. Oxygen atom has 8 protons and 8 neutrons so, its mass no. is
 (8+8=16) 16 amu .