Q.8:- Explain with examples (i) Atomic number, (ii) Mass number, (iii) Isotopes and (iv) Isobars.
Give any two uses of isotopes.
(i) Atomic Number : The number of protons present in the nucleus of an atom is called atomic number. It is denoted by Z. e.g: i.e., atomic number = 20
(ii) Mass Number: The sum of the number of protons and neutrons present in the nucleus of an atom is called mass number. It is denoted by A. e.g. i.e., mass number = 40
(iii) Isotopes : The atoms of the same elements having same atomic number but different mass numbers are called isotopes, e.g. and
(iv) Isobars : The atoms having same mass number but different atomic number are called
isobars, e.g.: and
(v) Uses of isotopes : (i) As nuclear fuel: An isotope of uranium (U – 235) is used as a nuclear fuel.
(ii) In medical field : An isotope of cobalt is used in the treatment of cancer.