Unit 4 Flashcard review

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What is a physical change?

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A physical change is a change that affects one or more physical properties of a substance without altering its chemical composition. Examples include changes in state (like melting or freezing), shape (like crumpling paper), or size (like sharpening a pencil).

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What is a chemical change?

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A chemical change is a change that results in the formation of new chemical substances. It involves a chemical reaction and the breaking and forming of bonds. An example is milk going sour.

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What is rust?

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Rust is a chemical compound, primarily iron oxide, formed when iron reacts with oxygen and moisture in the environment. It is an example of a chemical change.

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What is decomposition in chemistry?

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Decomposition is a type of chemical reaction where a single compound breaks down into two or more simpler products. An example is the decomposition of hydrogen peroxide (2H2O2 → 2H2O + O2).

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What is the product of the reaction between iron and oxygen?

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The product of the reaction between iron (Fe) and oxygen (O2) is iron(III) oxide (Fe2O3).

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What is the formula for rubidium oxide?

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The formula for rubidium oxide is Rb2O.

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What is a synthesis reaction?

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A synthesis reaction is a type of chemical reaction where two or more simple substances combine to form a more complex product. For example, 2H2 + O2 → 2H2O.

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What is a single replacement reaction?

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A single replacement reaction is a type of chemical reaction where one element replaces another in a compound. For example, Zn + CuSO4 → ZnSO4 + Cu.

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What is a combustion reaction?

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A combustion reaction is a chemical reaction that occurs when a substance combines with oxygen, releasing energy in the form of light or heat. An example is the burning of methane: CH4 + 2O2 → CO2 + 2H2O.

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What is the difference between physical and chemical changes?

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Physical changes do not alter the chemical composition of a substance, while chemical changes result in the formation of new substances with different properties.