Search over 10,000 free study notes

First, what is a tangent? A line which touches a circle (or ellipse) at just one point. In our case (-3,2)
As it touches the line at one point, it is perpendicular the radius at (-3,2). Which implies...

More reactive halogens displace less reactive halogens. The more reactive halogens are those at the top of the group, as their outer electron shells (negatively charged) are closer to the nucleus (positiv...

Chi-squared is about establishing whether the difference in results between groups is likely to be due to chance, or due to some genuine difference in the groups' properties. It aims to answer the questio...

The iodine test - use a dropper to apply a little iodine onto a small sample of the food. If starch is present, the iodine will change colour from orange/brown to blue/black.

Cambridge interviews are nowhere near as scary (or weird!) as they are often reputed to be. Mostly, tutors are looking to see that you actually care about the subject in addition to being good at it. I fo...