Question

Give reasons:​
(i) Physical properties of isotopes are different.​
(ii) Argon does not react.

Answer 1

(i) Isotopes contain the same number of protons but differ in the number of neutrons. Isotopes are chemical element variants that differ in neutron number, despite the fact that all isotopes of a given element have the same number of protons in each atom. As a result, their physical properties differ.​ ​

(ii) The outermost shell of Argon has 8 electrons. It has its octet complete.​ Therefore, it does not react with other elements and behaves as a noble gas.