Question
A-B. Reactive Metals Transition Metals, and Rare Earth Elements (pp. 27-28 5. Why are sodium and potassium often stored in oil?
Answer
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Anthony
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Answer
Sodium and potassium are frequently kept in oil to inhibit their high reactivity with air and moisture.
Explanation
Sodium and potassium are highly reactive alkali metals. These elements have a single electron in their outermost energy level, something that renders them very reactive. For instance, when they are allowed to interact with air, specifically oxygen and moisture, sodium and potassium can react vigorously. The result of these chemical reactions is often the formation of metal hydroxides or oxides. Of note is the fact that these reactions can be extremely exothermic, releasing a substantial amount of heat. In rare cases, it may cause small explosions owing to the sheer energetic nature of the reactions. In a bid to prevent hazardous reactions stemming from their interaction with air and moisture, both sodium and potassium are often stored in oil. This technique of storage offers an oxygen-free and water-free environment — optimal storage conditions for these highly reactive alkali metals.