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JEE Main levelOne or more correct optionsDifficulty 2 of 3sb198

Which of the following statements about calcium oxide are correct?

AIt is a basic oxide.
BIt combines with $SiO X_{2}$ at high temperature to give $CaSiO X_{3}$ .
CIt reacts with water with evolution of much heat.
DIt dissolves in aqueous $NaOH$ because it is amphoteric.

Answer: A, B, C

CaO

is basic, slakes exothermically (

CaO + H X_{2} O Ca (OH) X_{2}

) and combines with acidic silica to give a silicate. It is not amphoteric and does not dissolve in alkali.

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