This question was unpopular but the few candidates that attempted it performed fairly well. However,
some candidates recorded the values on the burette for A and B instead of reading the values on the metre
rule as directed by the question. Some candidates evaluated b = A - B instead of h = B - A as instructed.
Among those that were able to determine b and V correctly did not record them to the required decimal
places.

The (b) part was well tacked, however, some omitted the phrase "from a fixed mass of gas" and/or

constant temperature in their definition of *Boyl**e**'s law. *

In part (a) the tasks required of the candidates include:

- reading and recording values of A, B and V in trend;

- evaluation of five values of h and *VI *to the required decimal places;

- recording the data in composite table;

- distinguishing graph axes, selecting reasonable scales, plating of points correctly and drawing

- line of best fit;

- determine the slope of graph using large-right angled triangle;

Stating the precautions to ensure accurate results as follows:

- A void parallax error on metre rule/burette

- Note and correct for zero error on metre rule

- Repeated readings (stated)

The expected response to part (b) is as follows:

Boyle's law states that for a fixed mass of gas, the pressure is inversely proportional to the volume, provided that the temperature is kept constant