Glucose makes up about 0.10% by mass of human blood. Calculate this concentration in molality. What further information would you need to determine the molarity of the solution?

Verified step by step guidance

Step 1: Understand the given information. You are given the mass percentage of glucose in blood, which is 0.10%. This means there are 0.10 grams of glucose in 100 grams of blood.

Step 2: Calculate the mass of the solvent (blood without glucose). Since the total mass is 100 grams and glucose is 0.10 grams, the mass of the solvent is 100 grams - 0.10 grams = 99.90 grams.

Step 3: Convert the mass of the solvent from grams to kilograms, as molality is expressed in moles of solute per kilogram of solvent. Therefore, 99.90 grams = 0.09990 kilograms.

Step 4: Calculate the number of moles of glucose. Use the molar mass of glucose (C6H12O6), which is approximately 180.18 g/mol. The number of moles of glucose is calculated by dividing the mass of glucose by its molar mass: 0.10 grams / 180.18 g/mol.

Step 5: Calculate the molality of the solution. Molality (m) is defined as the number of moles of solute per kilogram of solvent. Use the formula: molality = moles of glucose / kilograms of solvent.

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Molality

Molality is a measure of the concentration of a solute in a solution, defined as the number of moles of solute per kilogram of solvent. It is expressed in moles per kilogram (mol/kg) and is particularly useful in situations where temperature changes may affect volume, as it relies on mass rather than volume.

Molarity

Molarity is another way to express the concentration of a solution, defined as the number of moles of solute per liter of solution. It is expressed in moles per liter (mol/L) and is sensitive to changes in temperature and pressure, which can affect the volume of the solution.

Density of the Solution

To determine the molarity of a solution, one must know the density of the solution, which allows for the conversion between mass and volume. The density provides the mass of the solution per unit volume, enabling the calculation of the total volume of the solution when the mass of the solute and solvent is known.

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