6.2 Pure Substances and Mixtures

Which of the following is NOT a pure substance?

• Gold

• Water

• Air

• Diamond

What is the definition of a pure substance?

• A substance that contains only one type of atom.

• A substance that cannot be broken down into simpler substances.

• A substance that contains only one type of particle.

• A substance that is found naturally in the environment.

What is an alloy?

• A pure metal.

• A mixture of a metal with other elements.

• A compound of two or more metals.

• A type of plastic.

What does the purity of a mixture tell us?

• How much of a specific chemical is in the mixture.

• How many different elements are in the mixture.

• How easily the mixture can be separated.

• How strong the chemical bonds are in the mixture.

What is the boiling point of pure water?

• 0 degrees Celsius

• 100 degrees Celsius

• 104 degrees Celsius

• It depends on the purity of the water

What is a hazard?

• The chance of something causing harm.

• Harm that something may cause.

• The process of identifying risks.

• A way to control risks.

What is a risk assessment?

• The process of identifying the hazards involved in a practical investigation and deciding how to control them.

• The chance of a hazard causing harm.

• A type of chemical reaction.

• A way to separate mixtures.

What is a risk?

• The chance of a hazard causing harm.

• Harm that something may cause.

• The process of identifying hazards.

• A way to control hazards.

What is a salt?

• A pure substance that is found in the ocean.

• A compound that consists of metal atoms joined to non-metal atoms.

• A mixture of two or more different types of atoms.

• A type of acid.

What is neutralisation?

• A chemical reaction between an acid and an alkali, which produces a neutral solution.

• The process of separating a mixture into its components.

• The process of making an alloy.

• A way to test the purity of a substance.