Chemical Reactions Quiz

What is a chemical reaction?

• A process in which atoms of one or more substances rearrange to form one or more new substances

• A change in the physical state of a substance

• A process where substances are mixed without changing their chemical composition

• A change in temperature or pressure without forming new substances

Which of the following is a sign that a chemical reaction might have occurred?

• Change in color

• Change in volume

• Change in shape

• Change in position

What is released or absorbed during a chemical change involving thermal energy?

• Light

• Sound

• Heat

• Electricity

What is an example of a chemical change that releases light?

• A battery producing electricity

• A firefly glowing

• Ice melting

• Water boiling

What happens to atoms during a chemical reaction?

• Atoms remain in a fixed arrangement and do not change.

• Atoms rearrange and form new substances.

• Atoms disappear and new atoms appear.

• Atoms fuse into larger atoms.

What can cause the bonds between atoms to break during a chemical reaction?

• The atoms are always stationary.

• The atoms collide without enough energy.

• The atoms collide with enough energy.

• The bonds break randomly without any cause.

What is the result of a change in the arrangement of atoms in a substance?

• The substance maintains the same physical and chemical properties.

• The substance changes its state of matter.

• The substance changes resulting in different physical and chemical properties.

• The substance becomes a pure element.

What is a chemical equation?

• A. A mathematical formula used to calculate chemical properties

• B. A description of a reaction using element symbols and chemical formulas

• C. A type of chemical bond between atoms

• D. A laboratory procedure for mixing chemicals

What are the starting substances in a chemical reaction called?

• A. Catalysts

• B. Products

• C. Reactants

• D. Equations

What are the substances produced by a chemical reaction called?

• A. Mixtures

• B. Reactants

• C. Catalysts

• D. Products