Why Don’t Oil and Water Mix?
There are two main reasons why don’t oil and water mix even if they are put in the same container, both of which deal with these two substances on a very small scale. Everything around us is made up of tiny particles known as molecules. The way in which two substances interact depends on the molecules that make up the substances.
The first reason that water and oil don’t mix is because their molecules are packed differently. The molecules of water are packed very densely. This means if we take equal parts of water and oil, there will be more molecules of water than oil. This also means that it will always sink underneath the oil.
There is one more reason why they cannot dissolve with each other. Water molecules are positively charged. Since only opposites attract and oil has no charge at all, there is no force between the substances that allow them to mix. Therefore even if you stir a container with oil and water, they will eventually separate into two distinct layers.
THINGS TO DO
- Go to science experiments section and search for ‘Density Test’. Watch the experiment and try to do it yourself.
Head on to Chemistry for Kids for more such interesting chemistry videos and interactive articles.