EoS _1

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

• Melting ice

• Cutting paper

• Burning wood

• Mixing salt and water

2. 2. What is the product of the combustion of magnesium?

• Magnesium chloride

• Magnesium oxide

• Magnesium hydroxide

• Magnesium sulfate

3. Which of the following statements is true about a physical change?

• A new substance is formed.
  

• Energy is always released.
  

• The composition of the substance does not change.

• The change is irreversible.

4. What color flame is produced when magnesium burns?

• Red

• Blue

• Green

• White

5. Which of the following statements is true about a chemical change?

• The change is reversible.
  

• Energy is always absorbed.
  

• The composition of the substance remains the same.

• A new substance is formed.

6. What gas is formed when magnesium reacts with hydrochloric acid?

• Carbon dioxide

• Oxygen

• Hydrogen

• Nitrogen

7. What are some causes of corrosion?

• Exposure to moisture and air
  

• Exposure to sunlight and heat
  

• Exposure to magnets and electricity

• Exposure to plants and animals

8. 8. How can corrosion be prevented?

• By painting the metal surface
  

• By removing the metal from its environment

• By increasing the temperature of the metal

• By scratching the metal surface

9. What are alloys?

• Metals that have high resistance to corrosion.
  

• Metals that are lightweight and flexible.
  

• Metals that are mixtures of two or more elements, including at least one metal.

• Metals that are highly conductive of electricity.

10. Which metals do not corrode?

• Iron and Copper

• Aluminum and Zinc

• Gold and Silver

• Nickel and Tin