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Questions
Write scientific reason.
Sodium is always kept in kerosene.
In the laboratory, sodium is immersed in kerosene.
Solution 1
Kerosene contains sodium as:
- As a highly reactive metal, sodium interacts with water in a highly exothermic manner.
- It has a strong reaction with water and oxygen.
- It can generate much heat when it reacts with oxygen and water vapor in the atmosphere.
- To prevent this strong reaction, it is thus stored or maintained in kerosene.
Solution 2
- Sodium reacts with moisture present in air, even at room temperature, to form sodium hydroxide and hydrogen gas.
\[\ce{\underset{\text{Sodium}}{2Na_{(s)}} + \underset{\text{Water}}{2H2O}_{(l)} -> \underset{\text{hydroxide}}{\underset{\text{Sodium}}{2NaOH}_{(aq)}} + \underset{\text{Hydrogen}}{H_{2(g)}}}\] - The reaction is exothermic and therefore, the released hydrogen gas readily catches fire on exposure to air.
Hence, to prevent accidents, sodium is stored in kerosene.
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