### Mathematical Issues for Chemists

A brief outline of the mathematical issues faced by chemistry students.

### Reaction Rates

Explore the possibilities for reaction rates versus concentrations with this non-linear differential equation

### Catalyse That!

Can you work out how to produce the right amount of chemical in a temperature-dependent reaction?

# Concentrations

##### Age 16 to 18 Challenge Level:

A spectophotometric assay is made by mixing a salt solution, acid buffer, bacterial cells and an enzyme catalyst. Using your skills of proportional reasoning, work out the volumes of given reagents required to create the standard assay. There are two different types of question: one in which you find the missing volumes and another in which you find the missing concentrations. Type your answers into the boxes and check them or generate new questions using the buttons.

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NOTES AND BACKGROUND

Mixing solutions of given concentrations from reagents in other concentrations is an essential scientific skill in the laboratory. In this question we convert between various ways of representing concentration and practise the crucial skill of dilutions. Recall that a concentration of, for example, $3.2$M means $3.2$ moles per litre and that the molecular weight is the weight in grammes of 1 moles of a compound.