The subject of Chemistry requires some mathematical skills. The nature of the mathematical skills that accompany the new Chemistry A level means that, both for AS and A level, at least 20% of marks on examination papers will assess mathematical skills, within the context of the relevant chemistry. You are encouraged to see mathematical skills – almost all of which are mathematical ideas that they are familiar with from GCSE – as tools that can be applied in different chemical situations.
Let us first look at empirical and molecular formulae
TASK 1. Use the co-worked examples below to work out the answer to the question set.
TASK 2: Now try the following all by yourself. Use the same template as that above to work out your answers. Show your workings out.
TASK 3: Now lets us look at what a mole is, how to calculate numbers of moles from masses and molar masses and the Avogadro constant. Use the video below to help you.
TASK 4: Now try the following all by yourself. Ask if unsure.
TASK 5: Now let us look at using the ideal gas equation to work out numbers of moles and molar masses. Use the videos below to help you.
TASK 6: Now try the following questions yourself - the one immediately below and the ones on the link below this.
A 0.280g sample of a gas has a volume of 58.5 cm3, measured at a pressure of 120 KPa and a temperature of 70oC. Calculate the molar mass of the gas. remember to convert KPa to Pa (multiply by 1000), cm3 to m3 (divide by 1000000) and oC to K (add 273).