Question

A solution is made by dissolving4.87 g of potassium nitrate in waterto a final volume of 86.4 mL solution.What is the weight/weight % orpercent by mass of the solute?Use 1.00 g/mL for the density of the solution.Enter text here

Answer 1

The weight/weight % of solute = 5.3%

Step-by-step explanation

Given

Mass of solute (potassium nitrate) = 4.87 g

Volume of solvent (water) = 86.4 mL

Density of water = 1.00 g/mL

Required: Weight/weight% of the solute

Solution

Step 1: Covert the volume of water to mass

mass = density x volume

mass = 1.00 g/mL x 86.4 mL

mass = 86.4 g

Step 2: Calculate the weight/weight % of the solute

Mass % solute = [mass of solute/(mass of solute + mass of solvent)] x 100

Mass % solute = 4.87g/(4.87 + 86.4)

Mass % solute = 5.3%