Question

Which of the following boxes contains isotones? (Numbers in the box represents mass number)

• A. Box A
• B. Box B
• C. Box C
• D. Box B and Box C

Answer 1

The correct option is C

Box C

Isotopes - One of two or more atoms having the same atomic number but different mass numbers.

Cobalt=55, Cobalt=56, Cobalt=57 (each has 27 protons).

Isobar - Any of two or more kinds of atoms having the same atomic mass but a different atomic number.

Manganese-56, Iron-56, Cobalt-56

Isotones - One of two or more atoms whose nuclei have the same number of neutrons but different numbers of protons.

Manganese-56, Iron-57, Cobalt-58 (31 neutrons each).