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Question
Describe the reaction of potassium with water. Write the equation of the reaction involved.
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Solution
Potassium reacts violently with cold water to form potassium hydroxide and hydrogen gas. The reaction of potassium metal with water is highly exothermic (heat-producing), so the hydrogen gas formed immediately catches fire. Thus, potassium is a very, very reactive metal.
\[\ce{\underset{Potassium}{2K_{(s)}} + \underset{(Cold)}{\underset{Water}{2H2O_{(l)}}} -> \underset{Potassium hydroxide}{2KOH_{(aq)}} + \underset{Hydrogen}{H2_{(g)}} + Heat}\]
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