Concentrated Hydrochloric acid is commonly sold as 12.0 M HCL and its density is 1.18 g/cm^3 . Calculate: (a)the Molality of the solution. (b) the weight percent of HCL in the solution
1
Expert's answer
2013-06-10T11:03:12-0400
The molality, b, of a solution is the amount of substance (in mol) of solute, divided by the mass (in kg) of the solvent (not the mass of the solution): b = n/m
1 L of the HCl solution contains 12 mol of the HCl. The mass of HCl is: m(HCl) = n(HCl)*M(HCl) = 12 mol * 36.5 g/mol = 438 g=0.438 kg The mass of the solution is: m(solution) = V(solution) * d(solution) = 1 L * 1.18 kg/L = 1.180 kg The mass of the solvent (water) is: m(H2O) = m(solution) - m(HCl) = 1.180 - 0.438 = 0.742 kg
a) The molality of the solution is: b(solution) = 12 mol/0.742kg = 16.17 m HCl
b) The weight percent of HCL in the solution can be calculated according to the following equation: w(solute) = m(solute)/m(solution) w(HCl),% = (0.438 kg / 1.180 kg)*100% = 37.12%
Numbers and figures are an essential part of our world, necessary for almost everything we do every day. As important…
APPROVED BY CLIENTS
"assignmentexpert.com" is professional group of people in Math subjects! They did assignments in very high level of mathematical modelling in the best quality. Thanks a lot
Comments
Leave a comment