Show all your work and use the correct number of significant figures and units.
ID: 493543 • Letter: S
Question
Show all your work and use the correct number of significant figures and units.
1. A strontium chloride solution is made by mixing 0.323g of strontium chloride with 150.0 mL of water. Use the molar mass of SrCl2 given below if necessary.
Molar mass of SrCl2= 158.52g/mol
a. Determine the number of moles of strontium chloride used to make the solution.
b. Determine the mass (in kg) of solvent used to make the solution. Assume thst the density of water is 1.000g/mL.
c. Determine the molarity (in m or mol/kg) of strontium chloride in this solution.
Explanation / Answer
(a)
0.323 g / 158.52 g/mol = 2.04X10^-3 mol SrCl2
(b)
150.0 mL water has a mass of 150.0 g because the density is 1.000 g/mL so mass of water will be 0.150 kg.
(c)
Molarity = mol of SrCl2 / kg water = (2.04X10^-3 mol SrCl2) / (0.150 kg water) = 0.0136 mol /kg