Separating mixtures and solutions:

Chromatography

Mixtures and Solutions

Mixing colours

PURPLERED + BLUE =

YELLOW + RED = ORANGE

Colour Prediction Outcome

BLUE

BROWN

GREEN

BLACK

Share your ideas with others in the group.

Show others respect, even if you disagree with them.

Listen to another group member when she or he is speaking: do not interrupt.

Encourage others to speak.

Stay on the group’s task.

Help the group stay on task.

Do not allow yourself to be distracted.

Keep your voice low enough that it will not distract other groups.

• Allow others to present their ideas, even when you think you know the answers.

Group work guidelines

What to do

What to do

What to do

• The water soaks up into the paper, meets the sample of ink and dissolves it.

• As the water continues to soak through the paper it leaves the colour particles behind—heaviest first, lightest last.

• Each ink gives a unique pattern, almost like a fingerprint.

What happens and why?

Uses of chromatography

• Pharmaceutical Company: determine amount of each chemical found in new product

• Hospital: detect drug or alcohol levels in a patient’s blood stream

• Law Enforcement: to compare a sample found at a crime scene to samples from suspects

• Environmental Agency: determine the level of pollutants in the water supply

A chromatograph