Cockermouth School AQA GCSE Chemical Analysis

What is chemical analysis?

• Identifying unknown substances
• Analytical chemistry
• Identifying known substances
• Chemical experiments

In everyday language what is a "pure" substance?

• Made of one compound
• No additives
• A mixture
• Clean

In chemistry what is a "pure" substance?

• No additives
• A mixture
• Made of one element/compound only
• A formulation

How can pure substances be distinguished from impure ones?

• Melting/boiling points
• Colour
• Smell
• Temperature

Describe the melting and boiling points of pure substances

• Range of temperature
• Fixed
• Different temperature
• One very specific temperature

Describe the melting and boiling points of impure substances

• Fixed
• Range of temperature
• Different temperature
• One very specific temperature

What is a formulation?

• Milk
• A designed mixture
• Calculation
• A random mixture

Give an example of a formulation

• Chlorine
• Acetone
• Paint
• Oxygen

Name a process to separate the constituents of a mixture

• Oxidation
• Displacement
• Chromotography
• Combustion

In paper chromatography, what is the mobile phase?

• Pencil line
• Paper
• Ink
• Solvent e.g. water