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Question
During the reaction of some metals with dilute hydrochloric acid, following observations are made.
The reaction of sodium metal is found to be highly explosive
Explain this observation giving suitable reason.
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Solution
Hydrogen gas is evolved when sodium metal (Na) is reacted with dilute HCl. The reaction is of exothermic nature. Therefore, hydrogen catches fire accompanied by explosion.
`2"Na"("s") + 2"HCl" ("aq") -> 2"NaCl"("aq") + "H"_2("g")`
Remember : Sodium metal as such does not catch fire. It is the hydrogen gas evolved which burns since the reaction is highly exothermic in nature.
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