3 What is an isotope?

Answer 1

Definitively an isotope is an atom of an element with a different number of neutrons.

Carbon has three different isotopes.

viz. Carbon-12 ( 12-C) , Carbon-13 ( 13-C) , and Carbon-14 (14-C).

For each isotope

12-C ; 6 protons, 6 neutrons ; ( 6 + 6 = 12) and 6 electrons

13-C ; 6 protons, 7 neutrons ; ( 6 + 7 = 13) and 6 electrons

14-C ; 6 protons, 8 neutrons ; ( 6 + 8 = 14) and 6 electrons.

Each isotope remains the same element, because the number of protons does NOT change, and with the same atomic No. However, each isotope has a different Atomic Mass, the sum of protons and neutrons.

NB Do NOT confuse with Allotrope. An allotrope is an element which exhibits different physical characteristics. In the case of carbon , there are three allotropes viz., graphite, diamond and buckminster fullerene (footballene).

NNB In the case of carbon each isotope can exhibit each allotrope in any combination.

NNNB Most elements in the Periodic Table have isotopes.

Answer 2

An isotope is a variant of a chemical element that has the same number of protons but a different number of neutrons in its atomic nucleus. This results in different atomic masses for the isotopes of the same element. While isotopes exhibit similar chemical properties, they can have different physical properties and varying levels of stability, with some being radioactive. For example, carbon-12 and carbon-14 are both isotopes of carbon.