Question

Which of the following pairs are isobars ?

$\left(i\right){}_{26}^{58}A,{}_{28}^{58}B\left(ii\right){}_{35}^{79}X,{}_{35}^{80}Y$

Give reasons for your choice.

Answer 1

Isotopes - Isotopes are the elements having the same atomic number but the different mass number.
In given question, isotopes are ${}_{35}^{79}X,{}_{35}^{80}Y$. Here the atomic number is the same 35.

Isobars - Isobars are the elements having the same mass number but the different atomic number.
In given question isobars are

$\left(i\right){}_{26}^{58}A,{}_{28}^{58}B$ Here the mass number is the same 58.