Question

how will you show that the given reaction obeys law of conservation of mass caco3+2hcl-cacl2+co2+h2o(cl=40,c=12,o=16,cl=35.5)

Answer 1

Explanation:

CaCO3 + 2HCl -----> CaCl2 + H2O + CO2.

2.5g? g

Mass of CaCO3= 40+12+3(16)=52+ 48= 100.

Molar mass of CaCO3=100g.

Mass of CaCl2= 40 + 2(35.5)= 40+ 71= 111.

Molar mass of CaCl2=111g.

Mass of CaCO3 (g) Mass of CaCl2 (g)

For 100g of CaCO

3

​

, 111g of CaCl_2$$ is formed.

let for 2.5g of CaCO

3

​

, x g of CaCl

2

​

 is formed.

Thus, by cross multiplication,

x=111×2.5/100=2.775g=2.78g.