Question

1.5 g of ethane (C2H6) on complete combustion gave
4.4 g of CO2 and 2.7 g of H2O. Show that the results
are in accordance to the law of conservation of mass.​

Answer 1

Answer:

mol.wt. of C2H6=12×2+1×6=30g

mol.wt of O2=16×2=32g

mol.wt of CO2=12+16=28g

mol.wt of H2O=2+16=18g

2C2H6+7O2---->4CO2+6H2O

2×30. 7×32 4×28. 6×18

60g of C2H6 uses 224g of O2

therefore, 1.5g of C2H6 uses=(1.5×224)/56=5.6g of O2

2C2H6+7O2---->4CO2+6H2O

1.5g . 5.6g. 4.4g. 2.7g

according to the law of conservation of mass,

sum of reactant= sum of products

1.5g+5.6g=4.4+2.7

7.1g=7.1g