SSC
CHEMISTRY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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a physical change occurs
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a change of state occurs
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a change in mass occurs
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a chemical change occurs
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Detailed explanation-1: -Rust is a result of chemical reaction where iron gets oxidized in presence of oxygen and moisture to form iron oxide. The chemical reaction for rusting is: 4Fe + 3O2 → 2Fe2O3.
Detailed explanation-2: -Rust is nothing but Iron Oxide; a new substance formed out of the reaction. The colour of the surface of the iron also changes. Hence, rusting of iron is a chemical change.
Detailed explanation-3: -Iron reacts with oxygen in presence of water to give hydrated iron oxide which is known as rust. The change is an irreversible change. And hence, this is a chemical change.
Detailed explanation-4: -Rusting is an example of a chemical change. A chemical property describes the ability of a substance to undergo a specific chemical change. A chemical property of iron is that it is capable of combining with oxygen to form iron oxide, the chemical name of rust.