Question

Two class IX students, kaveri and Nalin , were asked to take 5.3g of sodium carbonate and 6 g of ethanoic acid to make 2.2g of carbon dioxide, 0.9g of water and 8.2g of sodium ethanoate. Kaveri followed the instructions but Nalin took the chemicals without measuring their amounts. (a)Whose activity do you think will be in agreement with the law of conservation of mass?
(b) State the law of conservation of mass. (c)Whose method do you like and why?​

Answer 1

Answer:

Let us start from the reactant side

In the reactant side we have sodium carbonate and ethanoic acid

Mass of sodium carbonate=5.3g (given)

Mass of ethanoic acid=6g(given)

Now total mass before reaction that is mass of reactants = (5.3g + 6g) = 11.3g

Now let us check product side

Mass of carbon dioxide = 2.2g (given)

Mass of water = 0.9g (given)

Mass of sodium ethanoate = 8.2g (given)

Now total mass after reaction that is mass of products = (8.2g + 2.2g + 0.9g) = 11.3g

Conclusion:

Total mass before reaction=total mass after reaction

Therefore the given observation is in agreement with the law of conservation of mass.