Question

What volume of CO₂ in liters must be dissolved in 300 cm³ of water in order to produce a 0.20 mol/dm³ carbonic acid solution? [Assume the molar volume of gas is 22.4 L.]

Answer 1

To create a 0.20 mol/dm³ carbonic acid solution in 300 cm³ of water, 0.060 moles of CO₂ are required. Since the molar volume of CO₂ at STP is 22.4 L/mol, the volume of CO₂ needed is 1.344 liters.

Step-by-step explanation:

The question asks about the volume of CO₂ needed to dissolve in water to create a certain molarity of carbonic acid solution. Since the concentration of the carbonic acid solution is given as 0.20 mol/dm³ and we have 300 cm³ of water, we first need to calculate the moles of carbonic acid required for the solution.

To calculate the moles of carbonic acid, we can use the formula:

Moles = Molarity × Volume

First, convert the volume from cm³ to dm³:
300 cm³ = 0.300 dm³ (since 1 dm³ = 1000 cm³)

Now, calculate the moles of carbonic acid:
Moles = 0.20 mol/dm³ × 0.300 dm³
Moles = 0.060 moles

The molar volume of CO₂ at standard temperature and pressure (STP) is 22.4 L/mol, which means that 1 mole of CO₂ gas occupies 22.4 liters at STP. To find the volume of CO₂ needed, we multiply the moles required by the molar volume:

Volume of CO₂ = Moles × Molar Volume
Volume of CO₂ = 0.060 moles × 22.4 L/mol
Volume of CO₂ = 1.344 liters

Therefore, 1.344 liters of CO₂ gas at STP must be dissolved in 300 cm³ of water to produce a 0.20 mol/dm³ carbonic acid solution.