Chemical Analysis

chromatography separate the mixture of dyes on the basis of their ----------------------------

• density
• solubility
• gravity
• boiling point

A pure substance shows ------------------ spot on chromat gram

• 0
• 1
• 2
• 3

The diagram shows the chromatogram for three colouring dyes and that for a brown marker. What dye(s) are contained in the marker's ink?

• purple and green
• purple and yellow
• purple only
• green and yellow

Tags

NGSS.MS-PS1-2

Why is Chromatography useful?

• It can be used as medicine.
• It can be used for finding clues at a crime scene
• It can be used to make bombs.
• It can reduce the lack of food and water.

Mixtures can be separated using chromatography.

• True
• False

Which ink is a mixture of different pigments? 

• red
• orange
• green
• black

This chromatogram shows five commercial dyes (X, P, Q, R and S). The pigment in dye Q Is known to cause cancer. Which dye(s) is/are safe for use?

• P only
• S only
• P and S
• P and X

Tags

NGSS.MS-PS1-2

Why must the base line be drawn in pencil and not pen?

• a) Pencil is good at keeping substances in place.
• b) Pencil is soluble in water
• c) Pencil is insoluble in water
• d) Pencil is not coloured

Tags

NGSS.HS-PS2-6

 If a substance is not attracted to the water what happens to the 'dot'?

• a) Dot moves to the top of the paper
• b) Dot does not move at all
• c) Dot moves to the left or right
• d) Dot moves down to the bottom of the paper

Ink can be separated by a method of -----------------------------------------------

• distillation

• filtration

• chromatography

• sedimentation