Question

A teacher has two cubes of sugar that are both the same size and shape. He adds cube A to a beaker filled with 100 mL of water, and the cube completely dissolves in the water. He then places cube B on a glass dish over a flame. He keeps the dish over the flame until cube B has turned completely black. Once cube B has cooled off, he adds it to another beaker filled with 100 mL of water. Cube B does not dissolve in water.
What does this demonstration indicate?

Answer 1

Answer:

Burning sugar results in a chemical reaction

Explanation:

Flammability, odor, and density are just a few examples of characteristic properties of a substance. A chemical reaction occurs when molecules interact with one another and the molecules change. For example burning sugar results in a chemical reaction because the properties of cube B changed when it was burned. This change in solubility shows that cube B must be a different substance than cube A because of the chemical reaction that occurred when cube B was burned.