SCIENCE
CHEMISTRY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Burning bread in the toaster.
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melting wax in a microwave.
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dissolving salt in water
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boiling water to make steam.
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Detailed explanation-1: -Answer and Explanation: Toasting bread is a chemical reaction because the heat applied to the bread causes a process called the Maillard reaction.
Detailed explanation-2: -The Maillard reaction (/maɪˈjɑːr/ my-YAR; French: [majaʁ]) is a chemical reaction between amino acids and reducing sugars that gives browned food its distinctive flavor.
Detailed explanation-3: -Acrylamide is the black, burnt stuff that can form on some foods that contain sugars and certain amino acids when cooked at high temperatures, such as frying, roasting, or baking (boiling and steaming usually don’t produce acrylamide).
Detailed explanation-4: -The trapped carbon dioxide makes the dough rise, and the alcohol evaporates during the baking process. This is an irreversible chemical change, because by consuming the sugar, the yeast has created new substances-carbon dioxide and ethanol-and the reaction cannot be reversed.
Detailed explanation-5: -Burning is a chemical change as new substance is formed with new properties and it cannot be reversed.