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Which among the following are physical o...

Which among the following are physical or chemical changes?
(a) Evaporation of petrol
(b) Burning of Liquefied Petroleum Gas (LPG)
`(c)`Heating of an iron rod to red hot
(d) Curdling of milk
`(e)`Sublimation of solid ammonium chloride

Text Solution

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To determine whether the given processes are physical or chemical changes, we will analyze each one individually based on the definitions of physical and chemical changes. ### Step-by-Step Solution: 1. **Evaporation of Petrol**: - **Analysis**: When petrol evaporates, it changes from a liquid to a gas. No new substances are formed; the chemical composition of petrol remains the same. - **Conclusion**: This is a **physical change**. ...
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