Observing The Colour Changes of a Named Transition Element

The Chemistry of Art > 4. The Transition Metals > Observing The Colour Changes of a Named Transition Element >

Perform a first-hand investigation to observe the colour changes of a named transition element as it changes in oxidation state

Aim: To investigate the colour changes associated with changes in the oxidation state of manganese

Method:

  • Specifics not needed
  • Prepare a solution of ion with a high oxidation state and a low oxidation state
  • Record their colours
  • Make the ion with a high oxidation state reduce
    • High Oxidiser
  • Make the solution with a lower oxidation state oxidise
    • High Reductor
  • Record the colour changes in between as these cause further oxidation states to occur

Accuracy:

  • Not largely accurate as the colours viewed are a qualitative measure and potentially subjective

Reliability:

  • Repeated multiple times to ensure consistent results

Validity:

  • Controlled
    • Solutions have identical moles
    • Identical amounts of solution added to achieve each oxidation state
  • Answers aim

Variables:

Independent:
Oxidation state of Manganese

Dependent:
Colour displayed by each Manganese oxidation state