Chemical Reactions

Which of the following is true about chemical reactions?

• They are accompanied by changes in energy.

• They form new substances with new properties.

• both A and B

• neither A nor B

Tags

NGSS.MS-PS1-2

In an endothermic reaction, energy is

• absorbed.

• released.

• converted to mass.

• synthesized.

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

Which of the following is NOT a physical property?

• melting point

• state of matter

• density

• flammability

Substances formed as a result of a chemical reaction are called

• catalysts.

• precipitates.

• products.

• reactants.

Tags

NGSS.MS-PS1-5

In an exothermic reaction, products have more energy than reactants.

• true

• false

Tags

NGSS.HS-PS1-4

Water boils at 100°C. This is an example of a chemical property.

• true

• false

Substances that enter into a chemical reaction are called products.

• true

• false

The ability to react with oxygen is an example of a chemical property.

• true

• false

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Another name for a chemical change is a chemical bond.

• true

• false

In a physical change, some of the physical properties of the substance may be altered and the chemical composition remains the same.

• true

• false

Tags

NGSS.MS-PS1-4