Question

question 1 (2 points)
what conversion factor can be written for a 0.50 m kbr solution?
0.50 mol kbr / 1 l h₂o
1 l kbr solution / 0.50 mol kbr
more than one of these
0.50 mol kbr / 1 l kbr solution
1 mol kbr / 0.50 l kbr solution

Explanation:

Step1: Recall molarity definition

Molarity (M) is defined as moles of solute per liter of solution. A 0.50 M KBr solution means there are 0.50 moles of KBr in 1 L of the KBr solution.

Step2: Analyze each option

• Option 1: $\frac{0.50\ mol\ KBr}{1\ L\ H_2O}$ is incorrect because molarity is based on volume of solution not volume of solvent.
• Option 2: $\frac{1\ L\ KBr\ solution}{0.50\ mol\ KBr}$ is the reciprocal of the correct molar - based conversion factor.
• Option 3: Only one of the correct forms is present among the options, so this is incorrect.
• Option 4: $\frac{0.50\ mol\ KBr}{1\ L\ KBr\ solution}$ is correct as it represents the molarity relationship.
• Option 5: $\frac{1\ mol\ KBr}{0.50\ L\ KBr\ solution}$ is equivalent to a 2 M solution, not 0.50 M.

Answer:

$\frac{0.50\ mol\ KBr}{1\ L\ KBr\ solution}$