Understanding Elements, Compounds & Mixtures

What is an element?

• A pure substance made up of two or more types of atoms.

• A pure substance made up of only one type of atom.

• A mixture of different substances.

• A substance that can be easily separated.

What is a compound?

• A single element.

• A mixture of substances.

• Two or more elements chemically joined together.

• A substance that cannot be broken down.

Which of the following is an example of a mixture?

• Water

• Salt

• Air

• Carbon dioxide

What happens when iron and sulphur are mixed?

• They form a new compound.

• They can be easily separated.

• They produce a gas.

• They change colour.

What is formed when magnesium reacts with oxygen?

• Magnesium sulphide

• Magnesium chloride

• Magnesium oxide

• Magnesium nitride

What is the main component of air?

• Oxygen

• Carbon dioxide

• Nitrogen

• Water vapour

What is the process called when air is separated into its components?

• Filtration

• Distillation

• Fractional distillation

• Evaporation

Which of the following is a chemical change?

• Ice melting

• Water boiling

• Iron rusting

• Steam condensing

What is the percentage of oxygen in air?

• 78%

• 20%

• 0.04%

• 1.96%

Who developed the periodic table in 1869?

• Albert Einstein

• Isaac Newton

• Dimitri Mendeleev

• Marie Curie