Question

(a) state the law of conservation of mass. (b) in a chemical reaction 4.2g of sodium hydrogen carbonate reacted with 3.0g of ethanoic acid, the products obtained were 4.1g of sodium ethanoate, 0.9g of water and 2.2g of carbon dioxide. show that these observations are in agreement with the law of conservation of mass. (c) state the postulates of Dalton 's atomic theory which can explain the law of conservations of mass.

Answer 1

(a)in every chemical reaction, total mass of all the reactants is equal to total masses of all the products ,(b) sodium hydrogen carbonate+ethanoic acid =sodium ethanoate+water+ carbon dioxide. 4.2+3.0=4.1+0.9+2.2, 7.2= 7.2 mass of reactant =mass of product. thus, law of conservation of mass is proved. The postulate of dalton's atomic theory which can explain the law of conservation of mass is :-atoms are indestructible and retain their identity in chemical reactions