How will you prove experimentally the law of conservation of mass?
The law of conservation of mass states that during in a physical or chemical change, the mass of products remains equal to the total of reactants.
For example: When 100g of mercuric oxide is heated, 92.6 g of mercury and 7.4 g of oxygen are obtained as products. i.e. HgO → Hg + O2
In this case mass of reactant =100g
Mass of products = Mass of Hg + Mass of O2 = 92.6 + 7.4 = 100g
Thus, we obtain Mass of product = Mass of reactants. This verifies the law of conservation of mass.
Take some lead nitrate and some sodium chloride.
Prepare a 5% solution of both in water.
Take a litte amount of solution of sodium chloride in a conical flask and some solution of lead nitrate in an ignition tube.
Hang the ignition tube in the flask carefully; see that the solutions do not get mixed. Put a cork on the flask.
Weigh the flask with its contents carefully.
Now tilt and swirl the flask, so that the solutions of lead nitrate and sodium chloride get mixed.
You will see that the mass remains the same.