Year 7 Mixtures Mid-Topic Quiz

Which of the following is an example of a pure substance?

• refined sugar

• sea water

• air

• paint

A solution consists of:

• solid particles suspended in water.

• two different solids ground into powder form and mixed.

• one substance dissolved in another.

• bubbles of gas in a liquid.

Iona and Ross were doing an experiment that involved adding potassium sulfate to water. They added one teaspoon of potassium sulfate to the water and stirred it, and all the powder dissolved. This means that potassium sulfate:

• is insoluble in water.

• is soluble in water.

• is an unstable substance.

• cannot be identified as soluble or insoluble from the information given.

When sugar dissolves in water, the water is known as the:

• Solution

• Solute

• Solvent

• Suspension

Muddy water looks murky because:

• The mud particles are soluble

• The mud is dirty

• the mud particles are spread out and suspended in the water.

• the mud particles have been pulled apart and spread through the water.

What word is used to describe how easily a substance dissolves in water?

• Mass

• Solubility

• Chromatography

• Density

Insoluble is:

• a substance that will not dissolve in water.

• substance that will dissolve in water.

• substance like honey.

• mixture

Name the solvent that will easily dissolve sugar.

• Oil

• Detergent

• Water

This is a list of substances that make up a typical cup of tea: tea bag, milk, water, sugar, and a cup.

Classify each substance as 'pure' or 'mixture'.

Groups:

(a) Pure Substance

,

(b) Mixture

• Cup (Glass)

• Tea

• Milk

• Sugar

• Water

Write a definition for 'mixture'.

Provide an example.