How many grams of water are made from the reaction of 4.0 grams of hydrogen gas with the given reaction 2H2+O2--->2H2O

The mass of water is 36 g.

Explanation:

Mass of hydrogen = 4 g

Mass of water = ?

Solution:

First of all we will write the balance chemical equation:

2H₂ + O₂ → 2H₂O

Number of moles of hydrogen = mass / molar mass

Number of moles of hydrogen = 4 g / 2 g/mol

Number of moles of hydrogen = 2 mol

Now we compare the moles of water with hydrogen from balance chemical equation.

H₂ : H₂O

2 : 2

Mass of water = moles * molar mass

Mass of water = 2 mol * 18 g/mol

Mass of water = 36 g

If the water oxygen is in excess than mass of water would be 36 g.