Notebook Theme

Experiment No. N

Analysis of Manganese(II) Acetate (Mn(CH₃COO)₂)

Aim

To determine the presence of anion and cation in the given salt

Preliminary Test

  • Odor: Vinegar-like
  • Texture: Crystalline
  • Color: White
  • Solubility: Soluble in water

Test of Anion

ExperimentObservationInference
Take 0.1 g salt + dilute H₂SO₄Colourless vapours with vinegar-like smell evolveCH₃COO⁻ may be present
Confirmatory Tests
Ester Test
Take 0.1 g salt in a test tube with ethanol and a little conc. H₂SO₄, then heat
Fruity odour of ethyl acetate is developedCH₃COO⁻ is confirmed
Ferric Chloride Test
Add neutral ferric chloride solution to the salt solution
Deep red colour appears; on heating it disappears and a brown-red precipitate formsCH₃COO⁻ is confirmed

Test of Cation

ExperimentObservationInference
Original solution + H₂S gas in presence of NH₄OHBlack or flesh-coloured precipitate is formedGroup IV cation may be present
Confirmatory Test
Sodium Hydroxide Test
Dissolve the precipitate in dilute HCl by boiling and add NaOH in excess
White precipitate forms first, then turns brown on standingPresence of Mn²⁺ is confirmed

Result

The given salt contains Mn²⁺ ions as cation and CH₃COO⁻ ions as anion. The salt is Mn(CH₃COO)₂.

Precautions

  1. Handle the chemicals with care.
  2. Don't use excess of chemicals.
  3. Keep the mouth of the test tube away from the face.