Which solution is more concentrated?
a) 1.0L of 1.0M aqueous solution, or
b) 1.0L of 1.0m aqueous solution
To determine which solution is more concentrated, we need to understand the difference between molarity (M) and molality (m).
Molarity (M) is a measure of the concentration of a solute in a solution, defined as the number of moles of solute per liter of solution. The unit M is often used for aqueous solutions.
Molality (m), on the other hand, is a measure of the concentration of a solute in a solution, defined as the number of moles of solute per kilogram of solvent. The unit m is often used for non-aqueous solutions.
In the given options:
a) 1.0L of 1.0M aqueous solution means that there is 1.0 mole of solute dissolved in 1.0 liter of solution.
b) 1.0L of 1.0m aqueous solution means that there is 1.0 mole of solute dissolved in 1.0 kilogram of solvent.
Since both options have the same amount of solute (1.0 mole), the difference lies in the amount of solvent. Here, option a) has 1.0 liter of solution as the solvent, while option b) has 1.0 kilogram of solvent.
Since 1.0 kilogram is greater than 1.0 liter, option b) has a greater volume of solvent. Therefore, option a) is more concentrated than option b) because it has the same amount of solute in a smaller volume of solvent.
Hence, option a) is the more concentrated solution.