Which element is classified as a noble gas? o n cl xe

The correct answer is Xenon (Xe).

Explanation:

Noble gases are defined as the gases which have fully filled electronic configuration or stable electronic configuration.

From the given options:

Option 1: Oxygen (O)

The atomic number of this element is 8.

Electronic configuration of this element:

As, this is not the stable electronic configuration. Thus, it is not considered as a noble gas.

Option 2: Nitrogen (N)

The atomic number of this element is 7.

Electronic configuration of this element:

As, this is not the stable electronic configuration. Thus, it is not considered as a noble gas.

Option 3: Chlorine (Cl)

The atomic number of this element is 17.

Electronic configuration of this element:

As, this is not the stable electronic configuration. Thus, it is not considered as a noble gas.

Option 4: Xenon (Xe)

The atomic number of this element is 54.

Electronic configuration of this element:

As, this is a stable electronic configuration. Thus, it is considered as a noble gas.

Hence, the correct answer is Xenon (Xe).

Xenon (Xe) element is classified as a noble gas.

Explanation:

Noble gas are mono-atomic species with fully filled electronic configuration and are inert in nature.

Oxygen has atomic number of 8. Its electronic configuration is :

Nitrogen has atomic number of 7. Its electronic configuration is :

Chlorine has atomic number of 17. Its electronic configuration is :

All the above electronic configuration are not fully-filled.Hence they are not noble gases.They exist in diatomic form.

Xenon has atomic number of 54. Its electronic configuration is :

As, this is a fully filled and  stable electronic configuration. Thus, it is considered as a noble gas.