Halogens And Haloalkanes Flashcards
What is the test with Silver nitrate (AgNO3) supposed to do?
Used to identify which hydrogen halide is present in a solution
What precipitation gets produced as a result of the Silver nitrate test?
Fluorine: No precipitation
Chlorine: White precipitate
Bromide: Cream precipitate
Iodine: Pale yellow precipitate
What is the role of the nitric acid used in silver nitrate?
To react with any carbonates (CO3/2) to prevent the silver from reacting with it to make Ag2CO3 and mask the desired result
How can the different precipitates be differentiated from each other if the colors look too similar?
Treating the precipitates with ammonia (NH3)
Results are:
F = Won’t have a precipitate
Cl = Use dilute ammonia (Easily diluted)
Br = Use concentrated ammonia (Difficult to dilute)
I = No reaction due to being to hard to dissolve with ammonia
How do all halogens exist?
As diatomic molecules (can’t be by themselves due to being too reactive and unstable as free radicals)
What are the main colors of each halogen in solid, liquid, or gas form?
Fluorine: Pale yellow (g)
Chlorine: Pale green/greenish (g), Clear when reacting w/ others
Bromine: Red (l), Brown/Orange(g), sometimes Yellow
Iodine: Grey(s), Purple(g), and Brown
What’s a good way to think of displacement reactions of halogens with other halogens?
Like how light reflects a specific color and absorbs others, same with displacement reactions where the color of the end of a reaction shows which free radical halogen is in the solution and which halogen was displaced
What are oxidizing agents?
Electron acceptors that take electrons from others and make them positive, decrease down halogen group
How do halogens displace each other in reactions?
The stronger/more electronegative/stronger oxidizer agent will displace/replace a lower oxidizing power (F>Cl, Cl>Br, etc.)
Colors of solution in test tube showing free halogens
Cl = Pale green/Clear
Br = Yellow
I = Brown
(Organic: Cl = no color, Br = Yellow, I = Purple)
