Chemical Reactions

Front

What is a chemical reaction?

Back

A process where substances (reactants) change into new substances (products) by breaking and forming bonds.

Front

What are reactants in a chemical reaction?

Back

The starting substances that undergo change during a chemical reaction.

Front

What are products in a chemical reaction?

Back

The new substances formed as a result of a chemical reaction.

Front

What is a sign of a chemical change?

Back

Unexpected color change, temperature change, formation of a precipitate.

Front

What is a physical change?

Back

A change that affects one or more physical properties of a substance without changing its chemical composition.

Front

How many atoms of an element are in a compound represented as X_nY_m?

Back

The number of atoms of element X is represented by 'n' and of element Y by 'm'.

Front

What does it mean when a substance loses transparency?

Back

It is often a sign of a physical change, not a chemical change.

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What is a precipitate?

Back

A solid that forms and settles out of a liquid mixture during a chemical reaction.

Front

What is the law of conservation of mass?

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In a chemical reaction, mass is neither created nor destroyed; it is conserved.

Front

What is an example of a physical change?

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Melting ice or boiling water.