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प्रश्न
Explain the term – ‘sublimation’. Is sublimation of naphthalene – a physical or a chemical change. Give reasons.
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उत्तर
It is the conversion of a solid – directly into gaseous (vapour) state and on cooling directly back to solid-state – without changing into a liquid state.
It involves a change of state-and hence it is a physical change.
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