Molar Volume Question (1 Viewer)

[policy]

Calcium hydroxide solution absorbs carbon dioxide gas (to form a precipitate of calcium carbonate). What volume
of a 1.35mol/L solution is needed to dissolve 25mL of carbon dioxide at 25°C and 100 kPa?

Thanks!

 

[dcosmo]

Ca(OH)2(s) + CO2(g) - CaCO3(s) + H2O(l)

Need to calculate the number of moles of CO2 to start. For this use:

PV = nRT - ideal gas law

P = pressure (absolute pressure in Pascals), V = volume (litres), n = no of moles of gas, R = universal gas constant, T = temp in degrees Kelvin

make n the subject. Therefore:

n = PV / RT = 100000 x 0.025 / (8.314 x 298) = 1.026 moles of CO2. This is the number of moles of CA(OH)2. Will be easy to calculate the volume from the concentration of calcium hydroxide now.