Question

Ex. Q.1.c. What is meant by atomic mass number ? Explain how the atomic number and mass number of carbon are 6 and 12 respectively.

Answer 1

The total number of protons and neutron in an atom is the atomic mass number of that element.
Atomic mass number = number of protons + number of neutrons.
Atomic number = number of protons = number of electrons.It is denoted by Z.
Mass number = number of protons + number of neutrons. It is denoted by A.
For example : Carbon atom its, Number of proton = 6 Number of neutrons = 6
Number of electron = 6
Atomic number(Z) = number of protons = number of electrons = 6.
Mass number(A) = number of proton + number of neutrons = 6 + 6 =12.