Chemical Equations

Front

What is the little number written below an element in a chemical equation called? Example: H₂

Back

Subscript

Front

Which of the following is NOT a sign of a chemical change? A sudden release of heat, Bubbles forming, Two liquids mixed creating a precipitate, Melting in the hot sun

Back

Melting in the hot sun

Front

Is the following equation balanced? 2C₂H₂ + 5O₂ --> 4CO₂ + 2H₂O

Back

Yes

Front

Which of the following equations are correctly balanced? 1) 12CO₂ + H₂O --> C₆H₁₂O₆ + O₂ 2) CO₂ + 9H₂O --> C₆H₁₂O₆ + O₂ 3) CO₂ + H₂O --> 3C₆H₁₂O₆ + O₂ 4) 6CO₂ + 6H₂O --> C₆H₁₂O₆ + 6O₂

Back

6CO₂ + 6H₂O --> C₆H₁₂O₆ + 6O₂

Front

How many Hydrogen are in 4H₂O?

Back

8

Front

What is a chemical equation?

Back

A representation of a chemical reaction using symbols and formulas.

Front

What does a coefficient in a chemical equation represent?

Back

The number of molecules or moles of a substance.

Front

What is the law of conservation of mass?

Back

Matter cannot be created or destroyed in a chemical reaction.

Front

What is a reactant in a chemical equation?

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A substance that undergoes change during a chemical reaction.

Front

What is a product in a chemical equation?

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A substance that is formed as a result of a chemical reaction.