An amphoteric oxide dissolves in HCl to form a salt. The salt does not impart any colour to the flame and fumes in moist air. The oxide is

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An amphoteric oxide dissolves in HCl to form a salt. The salt does not impart any colour to the flame and fumes in moist air. The oxide is
A. `BaSO_2`
B. MgO
C. BeO
D. CaO


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Salim Ahmed Kawsar

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Correct Answer - C
Be does not impart any colour to flame. Its oxide BeO is amphoteric in nature. With HCl it forms `Be_2.BeCl_2` fumes in moist air because of formation of HCl again.
`BeCl_2+2H_2OtoBe(OH)_2+2HCl`

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