The concentration of KBr in a solution prepared by dissolving 2.10 g of KBr in 897 g of water is ________ molal.
A)2.46
B)0.0000207
C)0.0197
D)0.0167
E)0.0186

Question

Quizplus · Accepted Answer

Molality is defined as moles of solute per kilogram of solvent.

First, we need to convert the mass of KBr into moles:

2.10 g KBr × (1 mol KBr/119.0 g KBr) = 0.0176 mol KBr

Next, we need to convert the mass of water into kilograms:

897 g H2O × (1 kg/1000 g) = 0.897 kg H2O

Now, we can use the molality equation:

molality = moles of solute/kg of solvent = 0.0176 mol KBr/0.897 kg H2O = 0.0197 molal

Therefore, the concentration of KBr in the solution is 0.0197 molal.

The Concentration of KBr in a Solution Prepared by Dissolving