DP1 Quiz Measurement and Gases 2012-10-03 Name …
Mark Scheme
…
1. Gas in a balloon is heated. State which of the following quantities will not change
A temperature
B pressure
C volume
D number of moles
2. 20 ± 2cm 3 of liquid is measured in a measuring cylinder and 10 ± 1cm 3 is poured away. The absolute uncertainty in the volume of liquid remaining in the cylinder is:
A 1cm 3
B 2cm 3
C 3cm 3
D 4cm 3
3. State which of the following units is NOT used to measure pressure:
A kgm -2
B
C mmHg atm
D kPa
4. State which of the following pieces of apparatus can NOT be used to give an accurate measure of volume of a liquid
A burette
B
C beaker pipette
D measuring cylinder

5.
6.
A balance which measures to 0.001g but is not zeroed correctly is:
A precise but not accurate
B accurate but not precise
C neither accurate nor precise
D both precise and accurate
The mass of a beaker is measured as 42.31
± 0.01g and the mass of a beaker containing a sample of iron is measured as 42.61
± 0.01g. The minimum mass of the iron is:
A
B
C
0.28g
0.29g
0.30g
D 0.31g
7. Magnesium metal was added to dilute hydrochloric acid, giving magnesium chloride and hydrogen. The masses of the magnesium, volume of hydrochloric acid and volume of hydrogen were measured. State which measurement would have the smallest uncertainty:
A
B mass of magnesium volume of hydrogen
C volume of hydrochloric acid
D amount of magnesium chloride

8. Calculate the number of atoms in 5 moles of oxygen molecules.
…… 2 atoms in each molecule × 5 moles of molecules × Avogadro’s number =
2 × 5 × 6.02×10 23
= 6.02×10 23 atoms
……… [1]
9. The temperature of gas in a closed container increases from 300K to 400K. State 2 reasons that the pressure will increase by referring to the movement of the particles of the gas.
1. … the particles move with higher speed
………
2. …the particles hit the walls of the container more often ………[2]
10. Calculate the molar mass of calcium carbonate, CaCO
3
.
………
M r
(CaCO3) = 40 + 12 + (3 × 16) = 100 molar mass = 100 gmol -1 …… [2]
11. The molar mass of carbon dioxide is 44gmol -1 . Calculate the mass of 0.1mol.
……… mass = 0.1 × 44 = 4.4g ………………………… [1]
12. Calculate the volume of 0.1mol of carbon dioxide at a pressure of 100kPa and a temperature of 27C. Assume that carbon dioxide behaves as an ideal gas at this temperature and pressure.
…………
PV = nRT
V = nRT/P
= 0.1×8.31×(27+273)×100
… [2]
13. State and explain whether carbon dioxide would behave more or less like an ideal gas at a lower temperature and pressure.

………… at lower temperature and pressure it would behave more like an ideal gas as the interactions between molecules would be less significant when molecules are more widely spaced and moving more slowly
…… [2]
14. A balloon with a volume of 1dm 3 containing air at 27C is placed on a heater and increases in temperature to 77C. Assuming the pressure in the balloon is constant, calculate the new volume of the balloon.
…………
T1/T2 = V1/V2
V2 = V1×T2/T1
= 1×350/300
= 1.14dm
3 ……… [2]
15. Explain why the volume of the balloon increases when it is heated.
………
The particles of the gas move more quickly, and impact the walls of the balloon more often, changing the balance of pressure between the walls of the balloon and the gas, and pushing out the walls
……… [1]