- #1
IntegrateMe
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A solution of KCl has a density of 1.011 g/mL and has a concentration of 0.273 M. What is the molality of the solution? The molar mass of KCl is 74.5513 g.
So first I got g of KCl solute:
.273 (m) * 74.5513 (g/m) = 20.35 g
Total mass of solution = 1020.35g (since 1000g solvent per .273m solute).
Now density = mass/volume
Thus, volume = mass/density:
V = 1020.35 (g) / 1.011 (g/ml) = 1009 mL or 1.009 L
Now, molarity = moles/volume
So, M = .273/1.009 = .271
However, the accepted solution says .276 and does the problem differently, so I'm having trouble understanding if this is the correct or incorrect way of doing things.
Thank you!
So first I got g of KCl solute:
.273 (m) * 74.5513 (g/m) = 20.35 g
Total mass of solution = 1020.35g (since 1000g solvent per .273m solute).
Now density = mass/volume
Thus, volume = mass/density:
V = 1020.35 (g) / 1.011 (g/ml) = 1009 mL or 1.009 L
Now, molarity = moles/volume
So, M = .273/1.009 = .271
However, the accepted solution says .276 and does the problem differently, so I'm having trouble understanding if this is the correct or incorrect way of doing things.
Thank you!