Answer:
A. Show that the total of the masses of the starting substances equals the mass of the mixture.
Explanation:
Law of conservation of mass:
According to the law of conservation mass, mass can neither be created nor destroyed in a chemical equation.
This law was given by French chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.
For example:
In given photosynthesis reaction:
6CO₂ + 6H₂O + energy → C₆H₁₂O₆ + 6O₂
there are six carbon atoms, eighteen oxygen atoms and twelve hydrogen atoms on the both side of equation so this reaction followed the law of conservation of mass.
In a similar way if we have mixture of sugar and sand the total weight of mixture is equal to the weight of reactants.
sand + sugar + water → mixture
10g+5g+20 g = 35 g
