Ratio and proportion

Is there a temperature at which Celsius and Fahrenheit readings are the same?

The large rectangle is divided into a series of smaller quadrilaterals and triangles. Can you untangle what fractional part is represented by each of the ten numbered shapes?

Scientists often require solutions which are diluted to a particular concentration. In this problem, you can explore the mathematics of simple dilutions

Can you work out which drink has the stronger flavour?

Does Joseph have too many sheep in his flock...

A brief introduction to PCR and restriction mapping, with relevant calculations...

Ever wondered what it would be like to vaporise a diamond? Find out inside...

Do each of these scenarios allow you fully to deduce the required facts about the reactants?

When a mixture of gases burn, will the volume change?

What does the empirical formula of this mixture of iron oxides tell you about its consituents?