A candle's solid wax melts into liquid and then cools back into solid
A candle's solid wax melts into liquid and then cools back into solid. Deepika says melting is a chemical change, because the wax's form changed completely. Her brother says it is only a physical change. Who is right?
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Start thinking on Socho →More disagreements in Changes Around Us: Physical and Chemical
Adding a few drops of food colouring to a glass of water turns the water pinkAn iron rod is cut with a saw, and an identical rod is left out in the rain until it rustsSalt dissolves in water and disappears completelyMilk turns into curd, and curd does not turn back into milkTanya says fast changes are chemical and slow ones are physical — so iron rusting (slow) i