Answer: The correct answer is Option B.
Explanation:
Isotope is defined as the chemical specie which belong to the same element but differ in their molecular mass.
The isotopes have same atomic mass but differ in their mass numbers
Atomic number is defined as the number of protons or electrons that are present in a neutral atom.
Atomic number = number of protons = number of electrons
Mass number is defined as the sum of number of protons and neutrons that are present in an atom.
Mass number = Number of protons + Number of neutrons
Thus, isotopes of an element has same number of protons but they differ in the number of neutrons.
For Example: Chlorine has 2 isotopes, \(_{17}^{35}\textrm{Cl}\text{ and }_{17}^{37}\textrm{Cl}\)
- In \(_{17}^{35}\textrm{Cl}\) isotope:
Number of protons = 17
Number of neutrons = 35 - 17 = 18
- In \(_{17}^{37}\textrm{Cl}\) isotope:
Number of protons = 17
Number of neutrons = 37 - 17 = 20
Hence, the correct answer is Option B.
