Question: Beth made 2 solutions of different concentrations of water and citric acid. She put 50 milliliters of the first solution in cup X and 50 milliliters of the second solution in cup Y. When she put the cups on the balance, the balance looked as shown below. Which solution, X or Y, is more concentrated? Explain how you know which is more concentrated.
Reference answer: X. When equal amounts of 2 solutions are compared, the solution that is more concentrated will have the greater mass (weigh more). 50 milliliters of X has a greater mass than 50 milliliters of Y, so X must be more concentrated.

Student answer: Y, y because it have to be less.

Student answer: X, I chose x because x is more concentrated.

Student answer: X, well concentration is when you compare equal amount of volume of 2 solutions and one heavier it is more concentrated so that is how I know.

Student answer: Y, y has less material on bottom.

Student answer: X, they have the same amount of water but cup x has more citric acid.

Student answer: X, I know because when something is more concentrated it is also heavier.

Student answer: X, cup x is more heavier.

Student answer: X, because x is more heavier than cup y.

Student answer: X, because is heavier then y.

Student answer: X, cup x because it has more sugar in it.

Student answer: X, x because it is heavier.

Student answer: X, I know cup x is more concentrated because on the balance cup x is heavier and cup y is less concentrated.

Student answer: X, how I know is because concentrated means the heaviest.

Student answer: X, I know because when a solution has more solid, has a better taste, or weighs more it is more concentrated than the other one.

Student answer: X, x has less room to move around and y has less room to move around.

Student answer: X, I know that solution x is more concentrated.

Student answer: X, Because it weighed more than cup y.

Student answer: X, It is lighter.

Student answer: Y, is more concentrated because cup x is on the floor and that is not good, right?

Student answer: X, because it have more solid in it and it is heavier.

Student answer: X, because it is heavier.

Student answer: X, Because cup x is more heavier!

Student answer: X, the more concentrated is cup x is heavier.

Student answer: X, because the material gave it weight.

Student answer: X, well on a balance is on the bottom and if it can lift the other solution it is more concentrated.

Student answer: X, Cup x must have been more concentrated because it is heavier.

Student answer: X, usually the heaviest cup on the balance is the most concentrated cup.

Student answer: X, I think it is because it heavier. Remember I said I think.

Student answer: X, it is heavier.

Student answer: X, because it seem more concentrated then y.

Student answer: X, cup x because it is more heavy.

Student answer: X, I know cup x is the most concentrated because it weighs the most.

Student answer: X, I know solution x is more concentrated because it is heavier than solution y.

Student answer: X, They added more solute into the solution x than solution y. That is why solution x is heavier.

Student answer: X, because x is on the bottom of the weighing thing while y is on the top.

Student answer: X, because cup x weighs more than cup y.