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What would you observe when (a) a satu...

What would you observe when
(a) a saturated solution of potassium chloride prepared at `60^(@)`C is allowed to cool at room temperature?
(b) an aqueous sugar solution is heated to dryness?
(c) a mixture of iron filings and sulphur powder is heated strongly?

Text Solution

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(a) When a saturated solution of potassium chloride prepared at `60^(@)`C is allowed to cool at room temperature, crystals of potassium chloride will be formed.
(b) Initially, sugar will obtained as water wil get evaporated. But on dry heating sugar gets charred and it turns back.
`C_(12)H_(22)O_(11)overset(triangle)(to)underset((Black))(12C)+11H_(2)Ouarr.`
(c) The black coloured compound, iron sulphide is formed when a mixture of iron filings and sulphur powder is heated strongly.
`underset("Iron filings")(Fe)+underset("Sulphur powder")(S) overset(triangle)(to) underset("Iron sulphide")(FeS)`
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