Isotopes, Isobars and Isotones

Consider the following statements $(\mathrm{X}$ and $\mathrm{Y}$ stand for two different elements$)$

$\mathrm{I}.$ $32{\mathrm{X}}^{65}$ and ${}_{33}\mathrm{Y}^{65}$ are isotopes.

$\mathrm{II}.$ $42X^{86}$ and $42Y^{85}$ are isotopes.

$\mathrm{III}.$ $85{\mathrm{X}}^{174}$ and $88{\mathrm{Y}}^{177}$ have the same number of neutrons.

$\mathrm{IV}.$ $92X^{235}$ and ${}_{94}\mathrm{Y}^{235}$ are isobars.

The correct statements are:

The triad of nuclei that is isotonic is

Atomic weight of boron is $10.81$ and it has two isotopes  ${}_5{}^{10}\mathrm{B}$ and ${}_5{}^{11}\mathrm{B}$ in nature. What must have been the ratio of number of atoms in them?

Which radioactive isotope is typically utilized to estimate the age of fossils?

What is the relationship between the initial element $P$, which disintegrates by $\alpha$-emission, and the final element $Q$, which undergoes two subsequent disintegrations by $\beta$-emission?

The triad of nuclei, which is isotone, is

In the decay process, select the incorrect statement $A\stackrel{-\alpha }{\to }B\stackrel{-\beta }{\to }C\stackrel{-\beta }{\to }D$

The number of radioactive isotope of Hydrogen and total number of isotopes of Hydrogen are:

The atomic mass of an element is not a whole number because

${}_{12}^{24}M{g}^{2+}$

is isoelectronic with

The triad of nuclei that is isotonic is

The triad of nuclei that is isotonic is

Which of the following are isotopes?

The nuclei, which are not identical but have the same number of nucleons, are called

Isotones have different physical and chemical properties as they have

The set of isoelectronic species is

Calcium atom and $C{a}^{2+}$ ions have

${}_{11}^{24}Na$ and ${}_{12}^{24}Mg$ are related to each other as
$$

The element ${}_{32}^{76}Ge$ is isotonic with

Two nuclei $\mathrm{A}$ and $\mathrm{B}$ are isotonic with mass numbers $15$ and $16$ respectively. If $\mathrm{A}$ contains $7$ protons, then the number of protons in $\mathrm{B}$ would be