C8 Gas Tests and Separating Mixtures FT (05/02/2026)

Required

1

A pure substance has to be an element

4.8.1.1

Required

1

A mixture is always an impure substance.

4.8.1.1

Required

1

Impure substances have higher boiling points

4.8.1.1

Required

1

Salt is put on ice to increase the melting point.

4.8.1.1

2

Identify 2 differences between pure and impure substances

4.8.1.1

Required

1

What happens to the melting point of water when impurities are added?

4.8.1.1

Required

1

Explain why salt is placed on roads in winter months?

4.8.1.1

1

4.8.1.1

5.5.A

Required

1

4.8.1.1

1

Simple distillation allows us to separate liquids with different boiling points.

4.8.1.3

1

How many substances are in dye A?

4.8.1.3

1

How many substances are in Dye B?

4.8.1.3

2

4.8.1.1

4.8.1.3

1

In chromatography, ink is the solvent.

4.8.1.3

1

Why is the start line drawn in pencil rather than pen?

4.8.1.3

1

Chromatography allows us to separate different elements in a compound.

4.8.1.3

1

In chromatography, the dyes are soluble in water.

4.8.1.3

2

4.8.1.3

8

Put the order of Chromatography in order

Carefully add the solvent to a level just below the ink spot, taking care not to splash the paper
Place a spot of ink on the pencil line
Cover the beaker and wait a few minutes
Suspend the filter paper in a beaker so it isn't touching the sides or the bottom
Lay the paper flat and leave it to dry

4.8.1.3

1

Match the gas test to its positive result

Draggable item		Corresponding Item
Hold a burning splint at the open end of a test tube of the gas		Limewater turns milky (cloudy)
Place a glowing splint in a test tube of the gas		Litmus paper is bleached and turns white
Shakes or bubble the gas through limewater

4.8.2.1

4.8.2.2

…

C8 Gas Tests and Separating Mixtures FT (05/02/2026)

A pure substance has to be an element

A mixture is always an impure substance.

Impure substances have higher boiling points

Salt is put on ice to increase the melting point.

Identify 2 differences between pure and impure substances

What happens to the melting point of water when impurities are added?

Explain why salt is placed on roads in winter months?

Simple distillation allows us to separate liquids with different boiling points.

How many substances are in dye A?

How many substances are in Dye B?

In chromatography, ink is the solvent.

Why is the start line drawn in pencil rather than pen?

Chromatography allows us to separate different elements in a compound.

In chromatography, the dyes are soluble in water.

Put the order of Chromatography in order

Match the gas test to its positive result

A pure substance has to be an element

A mixture is always an impure substance.

Impure substances have higher boiling points

Salt is put on ice to increase the melting point.

Identify 2 differences between pure and impure substances

What happens to the melting point of water when impurities are added?

Explain why salt is placed on roads in winter months?

Simple distillation allows us to separate liquids with different boiling points.

How many substances are in dye A?

How many substances are in Dye B?

Explain how the chromatogram shows that A is a pure substance and B is a mixture.

In chromatography, ink is the solvent.

Why is the start line drawn in pencil rather than pen?

Chromatography allows us to separate different elements in a compound.

In chromatography, the dyes are soluble in water.

What colours are in substance P?

Put the order of Chromatography in order

Match the gas test to its positive result