Chemical Reactions

Front

What is an exothermic reaction?

Back

An exothermic reaction is a chemical reaction that releases energy in the form of heat or light.

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NGSS.MS-PS3-4

NGSS.MS-PS3-5

Front

Identify the reactants in the chemical equation: Na + Cl₂ → 2NaCl.

Back

The reactants are sodium (Na) and chlorine (Cl₂).

Front

What are physical changes in matter?

Back

Physical changes are changes that affect one or more physical properties of a substance without altering its chemical composition.

Front

Is boiling water a chemical or physical change?

Back

Boiling water is a physical change.

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NGSS.MS-PS1-4

NGSS.MS-PS3-4

Front

What state of matter is characterized by molecules that are closely packed and vibrate in place?

Back

Solid.

Front

What is a chemical change?

Back

A chemical change is a process that involves the transformation of one substance into another, resulting in a change in chemical composition.

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NGSS.MS-PS1-2

NGSS.MS-PS1-5

Front

Give an example of an exothermic reaction.

Back

Combustion of fuels, such as burning wood or gasoline, is an example of an exothermic reaction.

Tags

NGSS.MS-PS1-5

Front

What happens to energy during an endothermic reaction?

Back

In an endothermic reaction, energy is absorbed from the surroundings.

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NGSS.HS-PS1-4

Front

What is the difference between reactants and products in a chemical reaction?

Back

Reactants are the starting substances that undergo a chemical change, while products are the substances formed as a result of the reaction.

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NGSS.MS-PS1-2

NGSS.MS-PS1-5

Front

What is the law of conservation of mass?

Back

The law of conservation of mass states that mass is neither created nor destroyed in a chemical reaction; it is conserved.

Tags

NGSS.MS-PS1-5