Gas Volumes

Question 1

What are the three different ways of measuring the volume of gas given off in a reaction?

Answer 1

• If an upturned burette or measuring cylinder is used it must be filled with water before it is turned upside down. The scale on a burette goes the opposite way to a measuring cylinder.
• If a balance is used a loose plug of cotton wool in the neck of the flask prevents a spray. The volume of gas produced can be calculated from the mass of gas produced.

Question 2

At room temperature and pressure, how many dm^3 does 1 mole of gas occupy?

Answer 2

24

Question 3

What is the equation for gas volumes?

Answer 3

Volume of gas = number of moles X 24

Number of moles = gas volume/24

Question 4

What is the limiting reactant?

Answer 4

The reactant that is used up first.