Chemical tests
Wet anions test
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Wet Cations Test
Since you cant use a flame test you have to use another method to test for anions
Testing for halide anions
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Testing for sulfate anions
add barium chloride solution- a white precipitate will form
carbonate anions
Add HCL--> co2 gas will be emitted which will turn limewater cloudy
chloride
bromide
iodide
add dilute nitric acid (aq) then silver nitrate (aq)
then add NH3 in excess
chloride; White precipitate
bromide; Cream precipitate
iodide; Light yellow precipitate
NH4+ can be identified by adding sodium hydroxide solution.
However, no precipitate is formed. Instead, heating the mixture produces ammonia gas, which turns red litmus paper blue.
The goal is to test if H2O is present
Testing for water
One way you can test for water is using Anhydrous Copper sulfate - It turns blue when water is added
CuSO4 + H2O = CuSO4 5 H2O
The H2O in the molecule is known as the water of crystalization
Gas Tests
Flame tests
To test cations you can use a flame test. Different elements turn different colors when exposed to a flame which can identify them
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Lithium; Bright red
Sodium; Yellow
Potassium; Lilac
Calcium; Orange
Copper; Green, Blue
Hydrogen, oxygen, and carbon dioxide can be tested by its affects on a lit splint. Ammonia and chlorine must be tested by its affects on litmus paper
Splint /Hydrogen, oxygen, and carbon dioxide Tests
Oxygen
When a splint just put out is exposed to oxygen it will relight
Hydrogen
If the gas is hydrogen a bit would light and you'd hear a Pop
Carbon Dioxide
A lit splint would go out
Ammonia and chlorine Tests
ammonia
Add sodium hydroxide to test tube, Add ammonium nitrate to test tube ,Light a Bunsen burner and damped litmus paper with water. Warm the solution in the test tube up with the burner and hold the litmus paper over the top
If the litmus paper turns blue there is ammonia
Chlorine
Get chlorine gas from the electrolysis of sodium chloride solution. Hold litmus paper over the bubbles and the chlorine gas should bleach it.
The litmus paper goes from blue to white