Oil and water are immiscible because they do not mix. This is because oil is non-polar and water is polar. Polar compounds tend to dissolve in water but not oil and versa versa. Hence the expression 'like dissolves like'.
To read more click here to download Dr Hal's fact sheet on Layered Liquids (900kb pdf file)
Welcome to Dr Hal's Backyard Science, experiments you can try at home. These are experiments that you can try in your garden or house with parental permission and supervision. Each of them comes with some health and safety instructions that an adult must read. The text is reproduced by kind permission of Education in Chemistry a journal of the Royal Society of Chemistry.
Let us know how you get on by emailing drhal@drhal.co.uk