Chemistry Test 1

Which of the following statements about chemical changes is correct?

• Chemical changes can be easily reversed.
• Chemical changes only occur in gases.
• Chemical changes do not affect the mass of substances.
• Chemical changes result in the formation of new substances.

Which of the following best describes a physical change?

• The mass of the substance increases.
• A new substance is formed.
• The chemical identity of a substance changes.
• The form of a substance changes, but its identity remains the same.

What happens to the identity of a substance during a physical change?

• It is altered temporarily.
• It becomes unrecognizable.
• It remains the same.
• It changes completely.

Which of the following statements accurately describes a physical change?

• The chemical identity of the substance changes.
• The substance undergoes a change in form, but its identity remains the same.
• A new substance is created during the process.
• The mass of the substance decreases.

What does the law of conservation of matter state?

• Matter cannot be created or destroyed.
• Matter can be created or destroyed.
• Matter is always conserved in chemical reactions only.
• Matter can change forms but not identity.

Which of the following is an example of a chemical change?

• Density
• Boiling point
• Burning wood
• Melting point

Which of the following statements is true regarding chemical properties?

• They require a chemical reaction to be determined.
• They can be observed without changing the substance.
• They are not useful in identifying substances.
• They are the same as physical properties.

What distinguishes an extensive property from an intensive property?

• Intensive properties depend on the amount of substance present.
• Extensive properties depend on the amount of substance present.
• Intensive properties are always measurable.
• Extensive properties depend on the type of substance.

Which of the following is true about heterogeneous mixtures?

• They have a uniform composition throughout.
• They can be separated into their components easily.
• They are always made of two or more elements.
• They do not retain the identities of their components.

Which of the following mixtures is an example of a homogeneous mixture?

• A salad
• Sand and salt
• Oil and water
• Sugar water