Sally's teacher tells her to find the masses of a sugar cube and a glass of water. Sally finds the masses to be 10 g for the sugar cube and 100 g for the glass of water. Then, the teacher tells her to put the sugar cube into the water. Sally puts the cube into the glass of water and watches as it dissolves. Then, the teacher tells Sally to estimate the new mass of the glass of sugar-water.

Question

What should Sally guess as the new mass of the glass of sugar-water?
A.
110 g
B.
50 g
C.
200 g
D.
90 g

Answer 1

To estimate the new mass of the glass of sugar-water after the sugar cube dissolves, we need to consider the masses of both the sugar cube and the glass of water.

Sally found the mass of the sugar cube to be 10 g and the mass of the glass of water to be 100 g. When she adds the sugar cube to the water, the mass of the sugar dissolving in the water does not disappear; instead, it just becomes part of the solution.

Therefore, the new mass of the glass of sugar-water can be calculated as follows:

Mass of water (100 g) + Mass of sugar (10 g) = 100 g + 10 g = 110 g

So, Sally should guess that the new mass of the glass of sugar-water is 110 g.

The correct answer is A. 110 g.