Chemical and Physical Reactions Quiz

Which of the following is a physical property of iron?

• Grey, heavy solid with a melting point of 1538°C

• Has a pH of 2

• Reacts with sulfur to form iron sulfide

• Reacts with oxygen to form iron oxide

What happens when potassium reacts with water?

• It forms a solid substance

• It produces hydrogen gas and a lot of heat

• It dissolves completely

• It forms potassium hydroxide and water

What is the process of neutralisation?

• When an acid and an alkali react to form a neutral solution

• Mixing two acids to form a basic solution

• Combining water with a base

• Mixing two acids to produce a gas

What is a chemical property of hydrochloric acid?

• It is a colorless liquid

• It reacts with magnesium to form magnesium oxide

• It has a pH of 2

• It is a grey, heavy solid

Which of the following is produced when magnesium reacts with hydrochloric acid?

• Magnesium oxide

• Magnesium sulfate

• Hydrogen gas

• Oxygen gas

What happens when an acid and an alkali are mixed together?

• They remain unchanged

• They react to form an acidic solution

• They form a gas

• They react to form a neutral solution

Which of the following is a characteristic of a chemical reaction?

• The reaction is often reversible

• No new substances are formed

• Changes only involve the physical state of the substance

• New substances are formed, and the reaction is often irreversible

Which of the following is an example of a physical reaction?

• Rusting iron

• Melting ice

• Burning wood

• Baking a cake

What is a common sign of a physical change?

• Emission of light

• Change in state

• Temperature change

• Formation of a new substance

The formation of a precipitate can be a sign of a chemical reaction, indicating a new substance has been formed from the reaction of two liquid solutions.

• Depends on the temperature

• False

• True

• Depends on the pressure