Calculating Gas Volumes and Masses at Room Temperature and Pressure

The video tutorial explains calculations involving gases at room temperature and pressure. It covers four examples: calculating the mass of carbon dioxide, the volume of methane, the volume of oxygen reacting with hydrogen, and the volume of carbon dioxide produced from methane combustion. Each example uses the concept of moles and balanced chemical equations to determine the desired quantities.

What is the first step in calculating the mass of a gas at room temperature and pressure?

• Determine the volume of the gas

• Calculate the number of moles

• Measure the temperature

• Find the relative formula mass

How do you calculate the number of moles of methane from its mass?

• Multiply the mass by the relative formula mass

• Add the mass to the relative formula mass

• Divide the mass by the relative formula mass

• Divide the mass by the volume

What is the volume of 1 kilogram of methane at room temperature and pressure?

• 500 decimeters cubed

• 1,000 decimeters cubed

• 1,500 decimeters cubed

• 2,000 decimeters cubed

In a reaction between hydrogen and oxygen, how many moles of oxygen are needed for 0.25 moles of hydrogen?

• 1 mole

• 0.125 moles

• 0.5 moles

• 0.25 moles

When 50 decimeters cubed of methane is burned, what volume of carbon dioxide is produced?

• 75 decimeters cubed

• 49.9 decimeters cubed

• 100 decimeters cubed

• 24 decimeters cubed