Q. When a nucleus with atomic number $Z$ and mass number $A$ undergoes a radioactive decay process :

Nuclei Report Error

A

Both $Z$ and $A$ will decrease, if the process is $\alpha$ decay

B

$Z$ will decrease but $A$ will not change, if the process is $\beta^{+}$ decay

C

$Z$ will increase but $A$ will not change, if the process is $\beta^{-}$ decay

D

$Z$ and $A$ will remain unchanged, if the process is $\gamma$ decay

Solution:

In $\alpha$-decay nuclear charge decreases by a factor of $2$ and mass decreases by a factor of $4$ and in $\beta$-decay no effect is there on the mass of nucleus but charge increases or decreases by a factor of $1$ and in case of $\gamma$-decay no change will be there on charge or mass.

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