Question

If 1.4 g of calcium oxide is formed by the complete decomposition of calcium carbonate, then the amount of calcium carbonate taken and the amount of carbon dioxide formed will be respectively (a) 2.2 g and 1.1 g
(b) 1.1 g and 2.5 g
(c) 2.5 g and 1.1 g
(d) 5.0 g and 1.1 g

Answer 1

a). is correct I think so

Answer 2

The amount of calcium carbonate taken is 2.5 grams and the amount of carbon dioxide formed is 1.1 grams.

Explanation:

• According to the law of conservation of mass, calcium carbonate $(CaCO^3)$ is decomposed to form carbon dioxide $(CO^2)$ and calcium oxide$(CaO)$.

                                               $c a c o^{3} \rightarrow c a 0+c o^{2}$

• According to option c, the mass of calcium carbonate is 2.5 grams and that of carbon dioxide is 1.1 grams. So,

                                               $2.5=C a O+1.1$

                                               $\text { Cao }=2.5-1.1=1.4 \text { grams.}$

Mass of Calcium Oxide is 1.4 grams.