How many grams of water are produced from the reaction of 1.26 mol of oxygen according to this equation?
2h2(g)+o2(g)=2h2o(g)

45.4 g

Explanation:

Data given:

mole of oxygen = 1.26 mol

mass of water = ?

Reaction Given:

     2H₂ (g) + O₂(g) > 2H₂O (g)

Solution:

To solve this problem we look for mole mole ratio oxygen to water we look for the chemical reaction

                    2H₂ (g) + O₂(g)   >  2H₂O (g)

                                    1 mole                  2 mol

So,

It is clear from the reaction that 1 mole oxygen gives 2 mole water then how many mole of water will produce by 1.26 moles of oxygen.

So apply unity formula

               2 moles H₂O ≅ 1 mole O₂

               X moles H₂O ≅ 1.26 mole O₂

Do cross multiplication

              X moles H₂O = 2 mol x 1.26 mole / 1 mole

              X moles H₂O ≅ 2.52 mol

So,

1.26 mole of oxygen produce 2.52 mole of water.

Now convert moles of water to mass

Formula will be used

      mass in grams = no. of moles x molar mass

molar mass of water (H₂O)

molar mass of H₂O = 2(1) + 16

molar mass of H₂O = 2 + 16 = 18 g/mol

put value in above equation:

           mass in grams = 2.52 mole x 18 g/mol

           mass in grams = 45.4 g

So,

1.26 moles oxygen produce 45.4 g water