GK
GENERAL SCIENCE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Liquid becomes fire
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Nothing happens to anything
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Dissovling wood, Melting fire, you know the usual.
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Dissolving sugar, melting ice, etc. Any change in appearacne but not a different substance.
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Detailed explanation-1: -Physical changes only change the appearance of a substance, not the chemical composition. Examples of physical changes: boiling water, breaking a glass, melting an ice cube, freezing water, mixing sand and water, crumpling of paper, and melting a sugar cube.
Detailed explanation-2: -1: Ice melting is a physical change. When liquid water (H2O) freezes into a solid state (ice), it appears changed; however, this change is only physical, as the composition of the constituent molecules is the same: 11.19% hydrogen and 88.81% oxygen by mass.
Detailed explanation-3: -Melting an ice cube. Boiling water. Mixing sand and water. Breaking a glass. Dissolving sugar and water. Sublimation of dry ice. Crumpling a paper bag.