Match the following List-I with List-II and choose the correct option.
List-I
(P) ⁴⁰₁₈Ar and ⁴⁰₁₉K
(Q) ¹²₆C, ¹³₆C and ¹⁴₆C
(R) ¹⁶₈O, ¹⁵₇N and ¹⁴₆C
(S) ¹⁹₉F, ³⁹₁₉K and ²³₁₁Na
List-II
(1) Isodiaphers
(2) Isotones
(3) Isotopes
(4) Isobars
Answer (1)
To match the concepts correctly, we first need to understand what each term means in the context of chemistry:
Isobars are atoms of different elements that have the same mass number but different atomic numbers. They have different numbers of protons.
Isotopes are atoms of the same element with the same atomic number but different mass numbers due to varying numbers of neutrons.
Isotones are atoms that have the same number of neutrons but different numbers of protons.
Isodiaphers relate to atoms with the same difference between the number of neutrons and protons.
Let’s match List-I and List-II with these definitions:
(P) ⁴⁰₁₈Ar and ⁴⁰₁₉K : These are isobars. They have different atomic numbers (18 and 19) but the same mass number (40).
(Q) ¹²₆C, ¹³₆C and ¹⁴₆C : These are isotopes of carbon. They have the same atomic number (6) but different mass numbers (12, 13, and 14).
(R) ¹⁶₈O, ¹⁵₇N and ¹⁴₆C : These are isotones. All these atoms have the same number of neutrons (8).
(S) ¹⁹₉F, ³⁹₁₉K and ²³₁₁Na : These are isodiaphers. When calculating neutrons minus protons, each gives unique results, but generally the category is less common in basic curriculum compared to the others.
Therefore, the correct matches are:
(P) with (4) Isobars
(Q) with (3) Isotopes
(R) with (2) Isotones
(S) with (1) Isodiaphers
