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Gas law AQA textbook question

This question has been asked previously, but there are no solutions, can anyone help?

A hand pump was used to raise the pressure of the air in a flask of volume 1.2x10^-4, without and then with the powder in the flask
Without the powder in the flask, the pressure increased from 110kPa
With 0.38kg of powder in the flask, the pressure increased from 110kPa to 141kPa

(a) show that the volume of air in the hand pump initially was 2.7x10^-5 m^3
(B) calculate the volume and the density of the powder
Reply 1
To answer a) we can use Boyle's law.

P1V1 = P2V2

note: we can assume P1 to be atmospheric pressure (~100kPa)

To answer b) we use Boyle's Law again.

P2V2=P3V3

We know V1 from a), we know P1 and P3 from the question so we can calculate V3.

The difference between V1 and V2 is equal to the volume of powder.

Density can be found using the usual formula p=m/V

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