What is the molal concentration of potassium bromide in a solution prepared by dissolving 2.27 g of potassium bromide in 897 g of water?
A)2.46
B)0.0213
C)0.0167
D)0.0000207
E)0.0186

Question

Quizplus · Accepted Answer

First, we need to calculate the number of moles of potassium bromide:

moles of KBr = 2.27 g / 119 g/mol = 0.019 moles

Then, we need to calculate the mass of water in kilograms:

mass of water = 897 g / 1000 = 0.897 kg

Finally, we can calculate the molality using the formula:

molality = moles of solute / mass of solvent (in kg)

molality = 0.019 moles / 0.897 kg = 0.0213 mol/kg

Therefore, the molal concentration of potassium bromide in the solution is 0.0213 mol/kg, which corresponds to choice B.

What Is the Molal Concentration of Potassium Bromide in a Solution