Analía Bellizzi – Chemistry Classes

Ronald Reagan Senior High School

IGCSE TESTS REQUIRED TO KNOW FOR YOUR EXAMS

ANION TEST TEST RESULT
CHLORIDE Cl
acidify with dilute nitric acid, then add aqueous silver nitrate
White precipitate
BROMIDE Br
acidify with dilute nitric acid, then add aqueous silver nitrate
Cream precipitate
IODIDE
I
acidify with dilute nitric acid, then add aqueous silver nitrate
Yellow precipitate
NITRATE
NO3
add aqueous sodium hydroxide, then aluminium foil; warm carefully
Ammonia produced (it will turn blue a damped ph or red litmus paper

SULFATE

SO42–

acidify, then add aqueous barium nitrate
white precipitate of BaSO4

SULFITE

SO32–

add dilute hydrochloric acid, warm gently and test for the presence of sulfur dioxide
sulfur dioxide produced will turn acidified aqueous potassium manganate(VII) from purple to colorless
CARBONATE
CO32–
add dilute acid
Effervescence, carbon dioxide produced
CATION TEST RESULT WITH NAOH SOLUTION TEST RESULT WITH AMMONIA SOLUTION
COPPER (II)
Cu2+
light blue ppt., insoluble in excess
light blue ppt., soluble in excess, giving a dark blue solution
IRON(II)
Fe2+
green ppt., insoluble in excess
green ppt., insoluble in excess
IRON(III)
Fe3+
red-brown ppt., insoluble in excess
red-brown ppt., insoluble in excess
CHROMIUM(III)
Cr3+
green ppt., soluble in excess
Content
ZINC
Zn2+
white ppt., soluble in excess, giving a colorless solution
white ppt., soluble in excess, giving a colorless solution
CALCIUM
Ca2+
white ppt., insoluble in excess
no precipitate. or very slight white precipitate.
ALUMINUM
Al3+
white ppt., soluble in excess, giving a colorless solution
white ppt., insoluble in excess
AMMONIUM
NH4+
ammonia produced on warming
N/A
GAS TEST RESULT
AMMONIA
Damped red litmus paper
Turn blue
CARBON DIOXIDE
Bubble it through LIME WATER
Turns Milky
HYDROGEN
Lighted splint
POPS
OXYGEN
Glowing splint
relights
CHLORINE
pH paper or litmus paper (any color)
bleaches them
SULFUR DIOXIDE
Acidified aqueous potassium manganate (VII)
(also called potassium permanganate)
Change from purple to colorless
Tests to identify gases
GasSymbol
Test
Results
Carbon dioxide
CO2
bubble gas through limewater (calcium hydroxide solution)

Turns limewater cloudy.

 

Hydrogen
H2
Put a lighted splint into a sample of the gas.

Burns with a “popping” sound

 

Oxygen
O2
Put a glowing splint into a sample of the gas.

Splint relights.

 

Chlorine
Cl2

Put a damp BLUE litmus paper, it will get red first and then bleach immediately.

 

Splint relights.

Ammonia
NH3
Put a damp RED litmus paper and it will TURN BLUE.

Splint relights.