| Inert gases | Normal elements |
| i | In the atoms of inert gases all the shells are completely filled including outermost shell. | In the atoms of normal elements, only the outermost shell is incomplete. |
| ii | They are stable and are chemically inert (i.e., chemically non-reactive) | They are unstable and are chemically reactive. |
| iii | They are included in the p-block of the modern periodic table. | They are included in the s-block as well as p-block of the modern periodic table. |
| iv | They are placed in zero group (Group 18) of the modern periodic table. | These elements are placed in groups 1, 2 and 13 to 17 of the modern periodic table. |
