Explain with examples
(a) Atomic number
Mass number
Isotopes

Explanation

(i) Atomic number : The atomic number of an element is the total number of protons present in the atom of that element. For Ex : Nitrogen has 7 protons in its atom. Thus, the atomic number of Nitrogen is 7.
(ii) Mass number : The mass number of an element is the sum of the number of protons and neutrons present in the atom of that element. For Ex : The atom of Boron has 5 protons and 6 neutrons. So, the mass number of baron is `5+6=11`
(iii) Isotopes : These are atoms of the same element having the same atomic number, but different mass numbers. For example, Chlorine has two isotopes with atomic number 17 but mass number 35 and 37 represented by
`{:(35,37),(Cl,Cl),(17,17):}`
(iv) Isobars : These are atoms having the same number, but different atomic number i.e., Isobar are atoms of different elements having the same mass number. For Ex : Ne has atomic number 10 and Sodium has atomic number. 11 but both of them have mass number.
22 represented by, `._(10)^(22)Ne, ._(11)^(22)Na`
Give any two uses of Isotopes :
Two uses of Isotopes :
One isotope of uranium is used as fuel in nuclear reactors
One isotope of Cobalt is used in the treatment of cancer.