Read the given chemical reaction.

C2H6 + O2 → CO2 + H2O

How many moles of H2O are produced during the complete combustion of 1.4 moles of C2H6?

The answer to your question is 4.2 moles of H₂O

Explanation:

Data

moles of H₂O = ?

moles of C₂H₆ = 1.4

Balanced chemical reaction

               2C₂H₆  +  7O₂   ⇒   4CO₂   +  6H₂O

Process

To determine the moles of H₂O, use proportions and the coefficients of the balanced chemical reaction.

              2 moles of C₂H₆ 6 moles of H₂O

             1.4 moles of C₂H₆  x

                                  x = (1.4 x 6) / 2

                                  x = 8.4/2

                                  x = 4.2 moles of H₂O

it means there are 3 atoms of oxygen