molarity is the number of moles per unit volume (L).
6.25 m means 6.25 moles per L of solution, or per 1221.9 g of solution.
Calculate the mass density accordingly.
What is the mass percent of an aqueous sodium hydroxide solution in which the molality of NaOH is 6.25m? The density of the solution is 1.2219 g/mL
3 answers
Do you have a 6.25m or a 6.25M solution? Mathmate's answer and definition is for 6.25M.
The correct answer for 6.25m is below.
m is molality and the problem states molality (not molarity).
molality = mols solute/kg solvent.
6.25m means 6.25 mols NaOH/kg solvent.
g = mols x molar mass = 6.25 x 40 = about 250; therefore, you have a solution of 250g NaOH in (1000 + 250) or 250 g NaOH in 1250 g solution.
mass% = (250/1250)*100 = ?about 20%
The correct answer for 6.25m is below.
m is molality and the problem states molality (not molarity).
molality = mols solute/kg solvent.
6.25m means 6.25 mols NaOH/kg solvent.
g = mols x molar mass = 6.25 x 40 = about 250; therefore, you have a solution of 250g NaOH in (1000 + 250) or 250 g NaOH in 1250 g solution.
mass% = (250/1250)*100 = ?about 20%
Thank you Dr. Bob.
1 answer