Tests For Negative Ions? Flashcards
What happens to limewater in the presence of CO2?
It turns cloudy.
How do you test for carbonates?
By adding acid to a sealed container, then bubbling the gas through limewater.
What does an acid and a carbonate make?
CO2
Water
Salt
What sort of test is used for Halide and Sulfate ions?
Precipitation tests.
What are the halide ions?
Chloride
Bromide
Iodide
What is added to find halide ions?
Dilute nitric acid and then silver nitrate solution.
What does a chloride produce in precipitate tests?
White precipitate.
What colour precipitate does a bromide produce?
A cream one.
What colour precipitate does an iodide produce?
Yellow.
How do you test for Sulfate ions?
By adding dilute HCL and then Barium Chloride solution.
What would a Sulfate ion produce in a test?
Barium Sulfate.
What colour is Baroum Sulphate?
White.
How would you distinguish between sodium bromide and sodium iodide?
You would add dilute nitric acid and then silver nitrate.
This will make precipitates.
Bromides make cream and iodised make yellow.
How would you distinguish between magnesium Sulfate and aluminium sulphate?
Add a few drops of sodium hydroxide.
This produces two white precipitates but aluminium’s dissolves
How would you distinguish copper nitrate and copper Sulfate?
You test for Sulfate ions
You add hydrochloric acid and barium chloride.
A Sulfate will produce barium Sulfate which is a white precipitate.
