MCQ
Alkali metals react with water vigorously to form hydroxides and dihydrogen. Which of the following alkali metals reacts with water least vigorously?
- A$Li$
- B$Na$
- C$K$
- ✓$Cs$
✓
Answer
Correct option: D.
$Cs$
$Li$ has very high enthalpy of hydration, therefore the reaction between $Li$ and water is highly exothermic but the energy evolved is consumed in fusion, vaporation and ionisation as a result reaction with water proseeds slowly.
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