Question

Which of the following is not correct?

• A. Nuclei of atoms participate in nuclear reactions
• B. ${}_{20}^{40}Ca$ and ${}_{18}^{40}Ar$ are isotones
• C. $1$ amu of mass defect is approximately equal to $931.5$ MeV
• D. Uranium $\left(U^{238}\right)$ series is known as $(4n+2)$ series

Answer 1

Answer: (B)

${}_{20}^{40}Ca$ and ${}_{18}^{40}Ar$ are isotones

Correct statements.

Nuclei of atoms particles in nuclear reactions

1 amu of mass defect is apporximately equal to 931.5 Mev.

Uranium $\left(U^{238}\right)$ series is also known (4n+2) series.

Incorrect statment

${}_{20}^{48}Ca$ and ${}_{18}^{40}Ar$ are isotones.

$\Rightarrow$Isotones are those which have same number of neutrons.

$\Rightarrow$ ${}_{20}^{48}Ca$ and ${}_{18}^{40}Ar$ are isobars as they have different atomic number but same atomic mass.