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Moles V – Gas Laws

Question 1

Calculate the volume occupied by one mole of a gas at 25 oC and 100 kPa.

 

Question 2

 

Calculate the pressure of a gas given that 0.2 moles of the gas occupy 10 dm3 at 20 oC.

 

Question 3

Calculate the temperature of a gas if 0.5 moles occupy 1.2 dm3 at a pressure of 200 kPa.

 

Question 4

 

Calculate the mass of a sample of carbon dioxide which occupies 20 dm3 at 27 oC and 100 kPa.

 

Question 5

 

Calculate the relative molecular mass of a gas if a 500 cm3 sample at 20 oC and 1 atm has a mass of 0.66 g.

 

Question 6

 

At 25 oC and 100 kPa a gas occupies a volume of 20 dm3. Calculate the new temperature of the gas if

  1. the volume is decreased to 10 dm3 at constant pressure.
  2. the pressure is decreased to 50 kPa at constant volume.

 

Question 7

10.0 g of calcium nitrate is heated at 100 kPa and a temperature of 300 oC, at which temperature it fully decomposes. Calculate

  1. the volume of nitrogen dioxide evolved
  2. the volume of oxygen evolved
  3. the total volume of gas evolved

Equation: 2Ca(NO3)2(s) à 2CaO(s) + 4NO2(g) + O2(g)

 

 

Question 8

Calculate the colume of oxygen produced at 298K and 100 kPa by the decomposition of 30 cm3 of 0.1 mol dm_3 H2O2.

Equation: 2H2O2(aq) à 2H2O(l) + O2(g)

 

Question 9

What mass of magnesium, and what volume of 2.0 moldm-3 hydrochloric acid, will be required to produce 100 cm3 of hydrogen gas at 298 K and 100 kPa?

Equation: Mg(s) + 2HCl(aq) à MgCl2(aq) + H2(g)

 

Question 10

0.52 g of sodium was added to 100 cm3 of water. Calculate:

  1. The volume of hydrogen evolved at 298 K and 100 kPa
  2. The concentration of the sodium hydroxide solution produced, assuming the volume of water does not change.

Equation: 2Na(s) + 2H2O(l) à 2NaOH(aq) + H2(g)

 

Question 11

A balloon has a mass of 0.5 g when completely deflated. When it is filled with an unknown gas, the mass increases to 1.7 g. You notice on the canister of the unknown gas that it occupies a volume of 0.4478 L at a temperature of 50 °C. You note the temperature in the room is 25 °C. Identify the gas.

 

Question 12

A gas consisting of only carbon and hydrogen has an empirical formula of CH2. The gas has a density of 1.65 g/L at 27.0 °C and 97858 Pa. Determine the molar mass and molecular formula of the gas.

 

Question 13

Container A holds N2 gas with a mass of 56.2 g and is 4.4 times the volume of container B which holds argon (Ar) gas at the exact same temperature and pressure. What is the mass of the Ar (in g) within container B?