Question

What is the percent MgSO4 by mass in a solution made form 16.0g MgSO4 and 100mL of H2O at 25C? the density of water at 25C is 0.997g/mL.

Answer 1

percent of the mass of the solution = mass of the solute / mass of the solution + mass of the solvent

here solute = MgSO4   which is given as 16.0g

solvent is H2O = which is given 100 mL

convert the volume of the solvent in to mass using the formula

density = mass / volume

mass = density x volume

mass of the water = 0.997 g/mL x 100 mL = 99.7 gram

nou put all the values in the above equation

% of the MgSO4 = (16.0 g / 16.0 g + 99.7 g) x 100

= (16.0 g / 115.7 g) x 100

= 13.83%