Question

\(\rm _6^{12}{C}\) and \(\rm _6^{14}{C}\); \(\rm _1^{1}{H}\) and \(\rm _1^{3}{H}\); \(\rm _{17}^{35}{Cl}\) and \(\rm _{17}^{37}{Cl}\) are examples of
1. Isotones
2. Isomers
3. Isotopes
4. Isobars

Answer 1

Correct Answer - Option 3 : Isotopes

The correct answer is Isotopes.

• \(\rm _6^{12}{C}\) and \(\rm _6^{14}{C}\), \(\rm _1^{1}{H}\) and \(\rm _1^{3}{H}\), \(\rm _{17}^{35}{Cl}\) and \(\rm _{17}^{37}{Cl}\) are examples of Isotopes.

• Isotopes 
  • Those elements that have the same atomic number but a different mass number are referred to as isotopes. Hence, Option 3 is correct.
  • Isotopes occur due to the presence of a different number of neutrons in elements having the same atomic number as mass number is the sum of the number of neutrons and protons.
  • Many but not all elements have isotopes.
  • The isotopes of hydrogen are protium (has one proton and no neutrons), deuterium (has one proton and one neutron), and tritium (has one proton and two neutrons).
  • The chemical properties of isotopes are the same because they have the same number of protons and hence the same number of electrons which determines the chemical properties of an element.

• Isobars
  • The atoms have the same mass number but a different atomic number.
  • For example, the atomic number of carbon and nitrogen is 6 and 7 respectively.
  • Carbon-14 an isotope of carbon has a mass number of 14 which is the same as that of nitrogen and hence carbon-14 and nitrogen are isobars.
• Isomers
  • In chemistry, isomers are molecules or polyatomic ions with identical molecular formulas — that is, the same number of atoms of each element — but distinct arrangements of atoms in space.
  • Isomerism is the existence or possibility of isomers.
  • Isomers do not necessarily share similar chemical or physical properties. 
• Isotones
  • Two nuclides are isotones if they have the same neutron number N, but different proton number Z.
  • For example, boron-12, and carbon-13 nuclei both contain 7 neutrons, and so are isotones.
  • Similarly, ³⁶S, ³⁷Cl, ³⁸Ar, ³⁹K, and ⁴⁰Ca nuclei are all isotones of 20 because they all contain 20 neutrons.