What is a chemical reaction?

• A process where only physical changes occur

• A process where substances are converted to different substances

• A process where energy is always absorbed

• A process where substances remain unchanged

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

What are the starting substances in a chemical reaction called?

• Inhibitors

• Catalysts

• Reactants

• Products

Tags

NGSS.MS-PS1-1

Which of the following is NOT a characteristic of a chemical reaction?

• Temperature change

• Formation of a precipitate

• Change in color

• Change in shape

Tags

NGSS.MS-PS1-2

In a chemical equation, what does the arrow represent?

• The equality of reactants and products

• The direction of the reaction

• The temperature of the reaction

• The speed of the reaction

What is the first step in balancing a chemical equation?

• Add a catalyst

• Change the subscripts

• Identify each element

• Check the net charge

Which type of reaction involves two or more substances combining to form a single new substance?

• Decomposition

• Combustion

• Single-replacement

• Synthesis

What is an example of a decomposition reaction?

• CaCO3 → CaO + CO2

• Na + Cl2 → NaCl

• Zn + HCl → ZnCl2 + H2

• C + O2 → CO2

In a single-replacement reaction, what happens?

• Two elements combine to form a compound

• A compound breaks down into simpler substances

• One element replaces a similar element in a compound

• Two compounds exchange ions

What is formed in a precipitation reaction?

• An insoluble solid

• A liquid

• A new element

• A gas

What is the result of an acid-base reaction?

• Formation of a precipitate

• Production of water

• Release of light

• Absorption of heat