August 2, 2021
In this I/GCSE Chemistry blog post, it will look into
- How to test for anions
- The expected results of the test
Tests for Anions
To test for carbonates add HCl and if there is carbonate present CO2 will be released, you can't test for CO2 using lime water.
CO3 (2-) + 2H(+) - CO2 + H2O
To test for sulfates add HCl and barium chloride solution BCl2
- if a white precipitate of barium sulfate is produced it means that the original substances was a sulfate
- the HCl is added to get rid of any traces of carbonate or sulfite. Ba + SO4 - BaSO4
To test for halides add HNO3 and silver nitrate solution.
Ag + Cl - AgCl : a chloride ion gives a white precipitate of silver chloride.
Ag + Br - AgBr : a bromide ion gives a cream precipitate of silver bromide.
Ag + I - AgI : a iodide ion gives a yellow precipitate of silver iodide.
That's all for this post!