Nature of Matter Elements Compounds and Mixtures

Which statement correctly compares elements, compounds, and mixtures?

1. All are made by physical mixing only.
2. Elements contain one type of atom, compounds have chemically combined elements, and mixtures have physically combined substances.
3. Compounds and mixtures are the same.
4. Elements are always gases.

Which of the following is an example of an element used in electrical wiring?

1. Copper
2. Water
3. Air
4. Carbon dioxide

Which separation method uses a magnet?

1. Distillation
2. Magnetic separation
3. Filtration
4. Evaporation

Which statement about mixtures is correct?

1. Their components lose their properties.
2. They always have a fixed composition.
3. Their components retain their individual properties.
4. They cannot be separated.

Which of the following is represented by a chemical symbol?

1. Water
2. Air
3. Iron
4. Salt solution

Which method is commonly used to separate salt from seawater?

1. Filtration
2. Evaporation
3. Magnetic separation
4. Handpicking

Which of the following is NOT a pure substance?

1. Oxygen
2. Copper
3. Water
4. Air

Which property distinguishes an element from a compound?

1. An element contains only one type of atom.
2. An element is always colourful.
3. An element is always a gas.
4. An element can always be dissolved in water.

Which of the following is a heterogeneous mixture?

1. Air
2. Salt solution
3. Sand and water
4. Vinegar

Which of the following is a homogeneous mixture?

1. Oil and water
2. Sand and water
3. Salt dissolved in water
4. Soil

Which method can be used to separate sand from water?

1. Filtration
2. Distillation
3. Sublimation
4. Crystallisation

Which of the following is a compound?

1. Iron
2. Nitrogen
3. Water
4. Air

Which of the following is a mixture?

1. Carbon dioxide
2. Oxygen
3. Air
4. Iron

A compound is formed when:

1. Two or more elements combine chemically in a fixed ratio.
2. Different substances are mixed physically.
3. Two liquids are stirred together.
4. A solid is heated.

Which of the following is an element?

1. Water
2. Oxygen
3. Salt
4. Air