Question

An isotone of ${}_{32}^{76}Ge$ is-

• A. ${}_{32}^{77}Ge$
• B. ${}_{33}^{77}As$
• C. ${}_{34}^{77}Se$
• D. ${}_{34}^{78}Se$

Answer 1

Answer: (B), (D)

${}_{33}^{77}As$
${}_{34}^{78}Se$

Atoms that have the same number of neutrons but differ in the number of protons are called isotones.
For example
${}_{32}G{e}^{76}{,}_{33}A{s}^{77}$ and ${}_{34}S{e}^{78}$ have same number (44) of neutrons, hence they are isotones.