Elements with same atomic number but with different mass numbers

Through this online GK question series, currentaffairsindia.info presents the most relevant model questions on General Knowledge. These questions are applicable to all UPSC exams, PSC Exams, Railway Recruitment Exams, Bank PO and clerical exams and various other competitive exams. Any comments/doubts are welcomed!! 

1. The elements with Same atomic number but with different Mass numbers are known as?
(a) Isobars
(b) Isotopes
(c) Isoterms
(d) None of these

Did you know

Isotopes are variants of a particular chemical element such that, while all isotopes of a given element share the same number of protons and electrons, each isotope differs from the others in its number of neutrons. For example, carbon-12, carbon-13 and carbon-14 are three isotopes of the element carbon with mass numbers 12, 13 and 14 respectively.