The document contains 5 mixed stoichiometry problems involving chemical reactions such as the reaction of hydrogen and oxygen to form water, sulfuric acid and sodium hydroxide reacting to form sodium sulfate and water, tin and hydrogen fluoride reacting to form tin fluoride and hydrogen, carbon dioxide and lithium hydroxide reacting in a spacecraft to form lithium carbonate and water, and sodium reacting with water to form sodium hydroxide and hydrogen. For each problem, there are multiple parts that require calculating quantities such as moles, masses, or grams of reactants and products using mole ratios from balanced chemical equations.