Physical and Chemical Changes

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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 cutting, melting, and dissolving.

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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 rearrangement of atoms. Examples include rusting, burning, and reacting with acids.

Front

What happens to the properties of a substance during a physical change?

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The properties of a substance may change in terms of appearance, state, or size, but its chemical identity remains the same.

Front

What happens to the properties of a substance during a chemical change?

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The properties of a substance change completely, and new substances with different chemical identities are formed.

Front

Give an example of a physical change.

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An example of a physical change is freezing water to make ice.

Front

Give an example of a chemical change.

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An example of a chemical change is the reaction of vinegar and baking soda, which produces carbon dioxide gas.

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What is a physical property?

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A physical property is a characteristic of a substance that can be observed or measured without changing its chemical identity. Examples include color, melting point, and density.

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What is a chemical property?

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A chemical property is a characteristic of a substance that describes its ability to undergo a specific chemical change. Examples include flammability and reactivity with acids.

Front

Is cutting a loaf of bread a physical or chemical change?

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Cutting a loaf of bread is a physical change.

Front

What is the state of mercury at room temperature?

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Mercury is a liquid at room temperature.