The two isotopes of elemental chlorine are:

The correct answer is Option 4.

Key PointsThe two isotopes of elemental chlorine

• Isotopes are variants of a particular chemical element that differ in neutron number, and consequently in nucleon number.
• All isotopes of a given element have the same number of protons but different numbers of neutrons in each atom.
• Chlorine has two common isotopes, both having 17 protons (as indicated by the atomic number 17).
• The two isotopes of chlorine are Chlorine-35 (with 18 neutrons) and Chlorine-37 (with 20 neutrons).
• The notations ³⁵C₁₇ and 37C17 indicate the mass numbers 35 and 37, respectively, while the atomic number remains 17 for chlorine.
• Therefore, the correct representation of the two isotopes of chlorine is 35C17 and 37C17.

Additional Information

• Isotopes of Chlorine:
  • Chlorine-35: This isotope has 17 protons and 18 neutrons. It is the more abundant isotope, making up approximately 75.77% of natural chlorine.
  • Chlorine-37: This isotope has 17 protons and 20 neutrons. It constitutes about 24.23% of natural chlorine.
• Applications of Chlorine Isotopes:
  • Environmental Studies: Chlorine isotopes are used in tracing the sources and chemical processes of chlorine compounds in the environment.
  • Radiodating: Chlorine isotopes are sometimes used in dating groundwater and ice cores, contributing to climate studies.
• Atomic Structure and Notation:
  • Atomic Number (Z): The number of protons in the nucleus of an atom. For chlorine, Z = 17.
  • Mass Number (A): The total number of protons and neutrons in the nucleus. For Chlorine-35, A = 35 (17 protons + 18 neutrons), and for Chlorine-37, A = 37 (17 protons + 20 neutrons).
  • Isotopic Notation: The format ^(A)_{Z}Element is used to denote isotopes, where A is the mass number and Z is the atomic number.