Which of the following is an isobaric pair?

The atoms $_6C^{13}$ and $_8O^{17}$ are related to each other as .......

The number of protons,neutrons,and electrons in the element $_{89}^{231}Y$ is:

State whether the following statements are true or false:
$(i)$ Isobars have different atomic numbers.
$(ii)$ $_{14}^{30}\text{Si}$,$_{16}^{32}\text{S}$ are isotones.
$(iii)$ Niels Bohr was the first to suggest that the atom is spherical.
$(iv)$ Rutherford's model is accepted as the nuclear model of the atom.

What are $_{17}^{35}Cl$ and $_{17}^{37}Cl$? Why?

The nucleus of the element having atomic number $25$ and atomic weight $55$ will contain