Why are noble gases called "safe" gases?

Noble gases are called "safe" gases because they are inert.

General Formulas and Concepts:

Explanation:

Because Noble Gases have filled their outer shell electrons fully, they tend not to form compounds with other elements or react with others to produce another compound.

Take Ne (neon) for instance. It's electron configuration is 1s²2s²2p⁶. The outer most shell is the 2p sublevel, and according quantum numbers, the 2p sublevel only has 3 spaces for 2 electrons each that it can hold. Therefore, Ne has a full outer shell and no electron spots to create a bond with other elements.

D) burning a candle

Explanation

When burning a candle no new substance is form.

We have both physical and chemical change occuring.

Physical part: Melting of the solid wax and evaporation of the liquid forms the physical change.

Chemical part: burning of the wax vapour forms the chemical change.

Explanation: