Suppose you want to make 100 grams of water.  How much hydrogen and Oxygen would you need to make 100 grams of water with nothing left over.  Explain.

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justaguide | College Teacher | (Level 2) Distinguished Educator

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The chemical formula of water is H2O. One molecule of water has 2 atoms of hydrogen and one atom of oxygen.

1 mole of water requires 1 mole of hydrogen (H2) and 0.5 moles of oxygen (O2).

The molar mass of water is 100/18

This requires 100/18 moles of hydrogen. As the molar mass of hydrogen is 2, it requires 200/18 = 100/9 g of hydrogen.

It requires 0.5*100/18 mole of oxygen. The molar mass of oxygen is 32. The mass of oxygen required is 800/9 g

It requires 100/9 g of hydrogen gas and 800/9 g of oxygen gas to make 100 g of water.