SCIENCE
PHYSICAL SCIENCES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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ice melting
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burning a piece of paper
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pounding a piece of gold into a coin
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a puddle of water evaporating
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Detailed explanation-1: -Burning of paper is a chemical change because as a result of burning, ash is formed as a new chemical substance. During burning, Carbon react with hydrogen and oxygen, turning them into Carbon dioxide ( CO 2 ) and water.
Detailed explanation-2: -Detailed Solution The burning of paper is an example of a chemical reaction because when it is burnt, it combines with oxygen to form smoke and ash. A chemical reaction is one that changes the chemical properties of a substance and gives off a new substance.
Detailed explanation-3: -As we burn paper, it changes into ash i.e., changes its chemical composition. Hence, it is a chemical change not a physical one. Burning of paper is a physical change.
Detailed explanation-4: -Physical changes involve changes in the form of a substance, but not its chemical composition. As we burn a paper, it changes to ash i.e. its chemical composition changes. Hence, it is a chemical change.
Detailed explanation-5: -Burning of paper and log of wood. Digestion of food. Boiling an egg. Chemical battery usage. Electroplating a metal. Baking a cake. Milk going sour. Various metabolic reactions that take place in the cells. More items