Ahydrogen-filled balloon is ignited and 1.50 g of hydrogen reacts with 12.0 g of oxygen. how many grams of water vapor form? (assume that water vapor is the only product.)

The balanced chemical reaction between hydrogen and oxygen to form water is given as:

From the balanced chemical equation it is clear that one mole of hydrogen reacts to give 1 mole of water.

Since, number of moles =

So, number of moles of hydrogen =

Mass of hydrogen =     (given)

Molar mass of hydrogen,

Substituting the values:

Number of moles of hydrogen =

Number of moles of water formed on reacting with of hydrogen is:

Number of moles of water =

Mass of water can be calculated by:

Number of moles of water =

Molar mass of water =

Substituting the values:

Hence, the mass of water vapor forms is .

every chemical equation adheres to the law of conservation of mass, which states that matter cannot be created or destroyed. therefore, there must be the same number of atoms of each element on each side of a chemical equation.