Halogen Identification Flashcards
What colour is chlorine in water
Pale green
What colour is bromine water
Orange
What colour is iodine water
Brown
What non polar solvent do you add to differentiate between iodine and bromine?
Cyclohexane
What colour does the top layer of chlorine go?
Green
What colour does the top layer of bromine go?
Orange
What colour does the top layer of iodine go?
Violet
What is added to halide solutions to test for them?
Dissolved in nitric acid then silver nitrate is added dropwise
Why is nitric acid used?
To prevent fake positives from carbonate ions
What colour does AgCl go?
White precipitate
What colour is AgBr?
Cream precipitate
What colour is AgI?
Yellow precipitate
If we add dilute ammonia to these solutions, which halide dissolves?
Chlorine
If we add concentrated ammonia, which halide dissolves?
Bromine
How are halide solutions provided?
Via salt solutions
What is disproportionating?
When the same element or compound in a reaction in oxidised and reduced
Cl2 + NaOH —> NaClO + NaCl + H2O
What reaction is this
The making of bleach
Cl2 + H2O —-> HClO + HCl
What reaction is this?
Water purification
What is a pro of water purification
Kills bacteria
What are two negatives of water purification?
-toxic gas and respiratory irritant
- forms carcinogenic chlorinated hydrocarbons
How do you test for the presence of ammonia ion?
Add NaOH and gently warm, then hold damp red litmus paper over the test and it will go blue in the presence of ammonia ions
