Question

In an experiment to verify the law of conservation of mass in a chemical reaction, four students A,B,C and D noted down the following observations of the difference in mass of the apparatus with the chemical before and after the chemical reaction.---A =4.2g ,B=3.8g ,C=0g and D =2.5g . which student performed the experiment correctly and why?

Answer 1

C performed the experiment correctly and the difference in mass calculated by him.is correct I.e. equal to 0
Law of conservation of mass says that mass is conserved in a chemical reaction and total mass is constant before and after the reaction.Hence the mass difference In apparatus before and after the reaction should be 0