Question

Solid sodium reacts violently with water, producing Heath hydrogen gas, and sodium hydroxide ( 2Na + 2H2O --> 2NaOH + 2H2 ). How many molecules of hydrogen gas are formed when 67.2 g of sodium are added to water?

Answer 1

Here is a worked example of a stoichiometry problem. When you obtain moles H2 gas, convert to molecules by remembering that 1 mole of H2 gas contains 6.02E23 molecules.
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