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Molarity Ranking Tasks - help10

Molarity is an expression of a solution's concentration. It expresses the concentration as a ratio of the number of moles of solute per liter of solution. Knowlege of these two quantities - moles of solute and liters of solution - allows one to determine the molarity.

There are three versions of this question. Here is one of the versions.
 

Version 1:

Three aqueous solutions are made by mixing varying masses of the same solute in varying amounts of water. Rank the solutions according to their molarity (M).
 

In this question, you must rank the three aqueous solutions according to their relative molarity. In doing so, you must consider their ratio of moles of solute per liter of solution. The volume of the solution is determined by the volume of water. The number of moles of solute is related to the given mass of solute (in grams). The solute is the same in all three solutions - NaOH. Both the volume and the mass of solute varies from solution to solution.

Decreasing the volume tends to increase the concentration. And increasing the mass of solute tends to increase the concentration. And so one would reason that the solution with the most mass and the least volume has the greatest concentration. And conversely, the solution with the least mass and the most volume would have the smallest concentration. Fortunately, these two statements are sufficient for ranking the three solutions according to molarity.