Chemical Analysis - created from Mind Map

Página 1

Tests

Testing for anions (-)

Testing for Cations

Oxygen

Carbon Dioxide

Hydrogen

Acid

Alkali

Water

Use glowing splint

Relights

Limewater

Turns clear to cloudy

Lit splint

Squeaky pop

Blue litmus paper turns red

Red litmus paper turn blue

Boils at 100C

Testing of halide ions - Group 7

Testing for Sulphate Ions

Testing for Carbonates

Halide Ions (Cl-, Br-,I-)

Add a few drops of dilute nitric acid to the halide ion solution followed by a few drops silver nitrate

Dilute nitric acid - remove impurtities especially carbonate

Precipitate formed:

Cl- = Silver Chloride = White precipitate

Br- = Silver bromide = Cream precipitate

I- = Silver iodide = Yellow precipitate

Add a few drops of dilute hydrochloric acid to the sulphate ion solution followed by a few drops of barium chloride

If sulphate is present, you will observe a white precipitate - Barium Sulphate

Add hyrdochloric acid - fizzing

Calcium carbonate + Hydrochloric acid = Calcium chloride + Carbon Dioxide + Water

A gas called Carbon Dioxide is produced

CaCO3 + 2HCl = CaCl2 + CO2 + H20

Flame Test

Precipitation Test

Platinum wire cleaned with concentrated HCl and done in a blue flame

Lithium chloride = Li+ = Red

Sodium chloride = Na+ = Yellow/Orange

Potassium chloride = K+ = Lilac

Calcium chloride = Ca2+ = Brick Red

Barium chloride = Ba2+ = Pale Green

Strontium chloride = Sr2+ = Strong Red

Copper (II) chloride = Cu2+ = Blue/Green