CAIE A-Level Chemistry Mathematical, Structural and Data Skills
Practise the calculation, graph, representation and supplied-data conventions used across CAIE Chemistry.
- Syllabus
- 2028–2030
- Course
- Chemistry 9701
- Level
- AS
Practise the calculation, graph, representation and supplied-data conventions used across CAIE Chemistry.
The model of the nuclear atom was first proposed by Ernest Rutherford. He developed this model on the basis of results obtained from an experiment using gold metal foil.
Tumbaga is an alloy of copper and gold. A sample of tumbaga was analysed. The mass spectrum of the sample is shown.

Calculate the percentage abundance of gold, x, in the sample of tumbaga.
(100-56.36-25.14)=18.5(0)
4(CH3)3CCHO is used in the synthesis of some antibiotics.
X, Y and Z are all isomers of (CH3)3CCHO.
A summary of some of the reactions and properties of X, Y and Z is shown in the table.

Draw the skeletal formula of Z.

M1: skeletal alkene group AND C5 structure
M2: one alcohol group
M3: branched chain AND capable of geometrical isomerism