Question

$X$ and $Y$ are the two atomic species:

	$X$	$Y$
Number of Proton	$8$	$8$
Number of Neutron	$8$	$10$

Select the correct statement about $X$ and $Y$.

• A. $X$ and $Y$ are isobars
• B. $X$ and $Y$ have different chemical properties
• C. $X$ and $Y$ have different physical properties
• D. $X$ and $Y$ are the atoms of different elements

Answer 1

The correct option is C $X$ and $Y$ have different physical properties

${}_8^{16}X$ and ${}_8^{18}Y$.

As $X$ and $Y$ have the same atomic numbers but have different mass numbers so they are isotopes. Isotopes have different physical properties (like melting point, boiling point, and the nuclei of some isotopes are unstable or radioactive) but have the same chemical properties.

So, the correct option is $C$.