Why we do not see the smell

We can not see the smell because the smell is the smallest substance that can not be seen with the naked eye. The smell floated in the air and made a floating motion to touch our noses. Smell can move far and wide, accompanied by air. Because hot air is lighter than cold air, it makes the hot air move better, so it carries more odors. Generally, on a hot day, the odor spreads better than on a cold day. When a floating scent touches the nose, it always sends data to the brain, making us aware of the smell and the sense of smell. Smell.