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13. Matter Very Simple. Year 13. 13. Matter Very Simple. %. Grade. Student target. Teacher Comment. Why does the balloon not expand?. www.phet.colorado.edu. m = constant T = constant. Boyle’s Law. m = constant T = constant. No term for type of particle , therefore independent!.
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13. Matter Very Simple Year 13
13. Matter Very Simple % Grade Student target Teacher Comment
m = constant T = constant Boyle’s Law
m = constant T = constant
m = constant p = constant
V = constant m = constant
unknown measurable
Avogadro Number • Number of particles in one mole of a substance • E.g. 2 g of H2, 32 g of O2
k • NA was determined in 1909 so k could be calculated • Determine k
Quick Check Questions • Have a go at Q1-6 for Thursday
Pg 100 Q1 • Show that the pressure of an ideal gas doubles if its volume is halved
Pg 100 Q2 • A gas cylinder contains 100 litres of oxygen at room temperature and a pressure of 30 atm. Show that the cylinder can provide 6000 litres of oxygen at atmospheric pressure
Pg 100 Q3 • A meteorological balloon has a volume of 2 m3 at ground level. Show that the designer should expect it to have a volume of 8 m3 at a height where the atmospheric pressure us 25 % of that at ground level, if the temperature remains the same.
Pg 100 Q4 • In fact, in Q3 the temperature falls to -30 oC compared to 20 oC at ground level. Show that the designer should expect the balloon to have a volume of about 6.6 m3 at a height when the atmospheric pressure is 25 % of that at ground level.
Pg 100 Q5 • One mole of any ideal gas occupies a volume of about 22 litres at room temperature and pressure. Show that a small matchbox of air contains about 1020 molecules.
Pg 100 Q6 • 28 g of N2 contains 1 mole of molecules. Show that at a temperature of 546 K the nitrogen will occupy a volume of 22 litres at a pressure of 2 atm.