Question

Calculate the no. Of moles and find out no. Of molecules (i.)12g of ozone gas
ii.)20g of H^2O^2
iii.)22g of sulphur oxide

Answer 1

Explanation:

1.  In a reaction 5.3 g of sodium carbonate reacted with 6 g of ethanoic acid. The products were 2.2 g of carbon dioxide, 0.9 g water and 8.2 g of sodium ethanoate. Show that these observations are in agreement with the law of conservation of mass carbonate.

Ans.

Sodium carbonate+Ethanoic acid→Sodium ethanoate+Carbon dioxide+Water5.3 g+6 g→8.2 g+2.2 g+0.9 g

        LHS                        RHS

        11.3 g        =        11.3 g

        (Mass of reactant) (Mass of product)

        This shows, that during a chemical reaction mass of reactact = mass of product.

2.  Hydrogen and oxygen combine in the ratio of 1 : 8 by mass to form water. What mass of oxygen gas would be required to react completely with 3 g of hydrogen gas?

Ans. Ratio of H : O by mass in water is:

        Hydrogen : Oxygen → H2O

        1 : 8 = 3 : x

        x = 8 × 3

        ∴ 24 g of oxygen gas would be required to react completely with 3 g of hydrogen gas...