Notebook Theme

Experiment No. N

Analysis of Magnesium Acetate (Mg(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
Confirmatory Test
If group-V is absent, add disodium hydrogen phosphate solution and scratch the inner walls with a glass rodA white crystalline precipitate of magnesium ammonium phosphate is formedMg²⁺ is confirmed

Result

The given salt contains Mg²⁺ ions as cation and CH₃COO⁻ ions as anion. The salt is Mg(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.