A student is comparing physical versus chemical changes using sugar cubes. Which part of the student's experiment illustrates a chemical change?

A
Melting a sugar cube using a hotplate

B
Burning a sugar cube in a flame

C
Dissolving a sugar cube in water

D
Crushing a sugar cube with a mortar and pestle

answer; the above statement is (true);

photosynthesis makes the glucose that is used in cellular respiration to make atp. the glucose is then turned back into carbon dioxide, which is used in photosynthesis. while water is broken down to form oxygen during photosynthesis, in cellular respiration oxygen is combined with hydrogen to form water.