Why is the law of conservation of mass true? a. all atoms at the start of a chemical reaction are present at the end of the reaction

b. All the molecules in a substance remain intact during a chemical reaction

c. The substances at the start of a chemical reaction gather more atoms to make up for those lost in the reaction

d. all molecules at the start of a chemical reaction are present at the end of the reaction

24 points and brainliest to anyone who can answer under 10 minutes with best ! the table below shows the role of different substances during photosynthesis. substance role during photosynthesis glucose stores chemical energy water combines with glucose to form carbon dioxide chlorophyll traps sunlight which of the following statements would correct one of the roles listed in the table? glucose combines with carbon to form water. chlorophyll reacts with light to produce carbon dioxide. water combines with carbon dioxide during photosynthesis. chlorophyll stores chemical energy needed for photosynthesis.

The molality of calcium chloride (cacl2) in an aqueous solution is 2.46 m. what is mole fraction of the solute?

Ineed ! i have no clue how to do this problem.