Question

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

Answer 1

Answer:

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.