Notebook Theme

Experiment No. N

Analysis of Strontium Fluoride (Sr(F)₂)

Aim

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

Preliminary Test

  • Odor: Odorless
  • Texture: Crystalline
  • Color: White
  • Solubility: Soluble in water

Test of Anion

ExperimentObservationInference
Take the salt and treat with concentrated H₂SO₄Colourless gas evolves and it etches glassF⁻ may be present
Confirmatory Test
Calcium Chloride Test
Treat salt solution with calcium chloride solution
White gelatinous precipitate formsPresence of F⁻ is confirmed

Test of Cation

ExperimentObservationInference
Original solution + Dilute HClNo reactionGroup I cation is absent
Original solution + Dilute HCl + H₂S gas (with NH₄Cl)No reactionGroup II cation is absent
Original solution + Dilute HCl + NH₄Cl solid + NH₄OHNo reactionGroup III cation is absent
Original solution + NH₄Cl + NH₄OH + (NH₄)₂CO₃White precipitate is formedGroup V cation may be present
Confirmatory Test
Ammonium Sulphate Test
Dissolve white precipitate in dilute acetic acid and add ammonium sulphate solution
White precipitateSr²⁺ is confirmed

Result

The given salt contains Sr²⁺ ions as cation and F⁻ ions as anion. The salt is Sr(F)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.