How to Find the Volume of a Gas

• What is the equation that links gas volume to moles?

  Volume = moles × 24
• What does the equation for gas volume apply to?

  Any type of gas, like chlorine or oxygen
• How do you calculate the volume of 3.5 moles of chlorine gas?

  3.5 × 24 = 84 decimeters cubed
• How do you find moles from a volume of 60 decimeters cubed of oxygen?

  60 ÷ 24 = 2.5 moles
• What is the first step to find the volume of 27 grams of water vapor?

  Find the moles using mass and relative formula mass
• What is the relative formula mass (Mr) of water (H2O)?

  18
• How do you calculate moles from 27 grams of water vapor?

  27 ÷ 18 = 1.5 moles
• What is the volume of 1.5 moles of water vapor?

  1.5 × 24 = 36 decimeters cubed
• What is the limiting reagent in a reaction with excess hydrogen and 18 decimeters cubed of nitrogen?

  Nitrogen is the limiting reagent
• How do you find moles of nitrogen from 18 decimeters cubed?

  18 ÷ 24 = 0.75 moles
• What is the molar ratio of nitrogen to ammonia in the reaction?

  1 to 2
• How many moles of ammonia are produced from 0.75 moles of nitrogen?

  0.75 × 2 = 1.5 moles
• What is the volume of 1.5 moles of ammonia?

  1.5 × 24 = 36 decimeters cubed
• What is the significance of the molar ratio when converting gas volumes?

  It allows direct volume conversion without moles
• How much hydrogen reacts with 4 decimeters cubed of nitrogen?

  4 × 3 = 12 decimeters cubed
• Under what conditions does the equation with the number 24 apply?

  At room temperature and pressure
• What happens to gas volume if temperature or pressure changes?

  Gas volume changes with temperature or pressure
• What is the only equation needed for exams regarding gas volumes?

  The equation with the number 24