posted by Michelle on .
A 19.9mL volume of a hydrochloric acid solution reacts completely with a solid sample of magnesium carbonate, producing 183mL of CO2 that is collected over water at 24.0 degrees C and 738 torr total pressure. The vapor pressure for water at 24.0 degrees C is 22.39 mmHg. What is the molarity of the hydrochloric acid solution?
MgCO3 + 2HCl ==> H2) + CO2 + MgCl2
Use PV = nRT to correct 183 mL CO2 at the conditions listed to STP You want to solve for n = number of mols CO2. Note that P = (738-22.39)/760 = ? atm.
mols CO2 @ STP/2 = mols HCl
M HCl = mols HCl/L HCl