QA Table

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TEST FOR CATIONS

 

Cation	Add sodium hydroxide solution, dropwise with shaking, until you observe no further change.	Add ammonia solution, dropwise with shaking, until you observe no further change.
Al3+	white ppt formed soluble in excess aq. NaOH to give colourless solution	white ppt formed insoluble in excess aq. NH3
Ca2+	white ppt formed insoluble in excess aq. NaOH	no ppt formed
Cu2+	blue ppt formed insoluble in excess aq. NaOH	blue ppt formed soluble in excess aq. NH3 to give a deep blue solution
Fe2+	dirty green ppt formed insoluble in excess aq. NaOH	dirty green ppt formed insoluble in excess aq. NH3
Fe3+	red-brown ppt formed insoluble in excess aq. NaOH	red-brown ppt formed insoluble in excess aq. NH3
Pb2+	white ppt formed soluble in excess aq. NaOH to give colourless solution	white ppt formed insoluble in excess aq. NH3
Zn2+	white ppt formed soluble in excess aq. NaOH to give colourless solution	white ppt formed soluble in excess aq. NaOH to give colourless solution
NH4+	colourless, pungent gas produced gas turned moist red litmus paper blue	--

 

TEST FOR ANIONS

 

Anion	Test	Observations
Carbonate (CO32-)	Add dilute nitric acid or hydrochloric acid	effervescence colourless, odourless gas produced gas formed white ppt with limewater
Chloride (Cl-)	Add dilute nitric acid, followed by silver nitrate solution	white ppt formed
Iodide (I-)	Add dilute nitric acid, followed by silver nitrate solution	yellow ppt formed
Sulfate (SO42-)	Add dilute nitric acid, followed by barium sulfate solution	white ppt formed
nitrate (NO3-)	Add sodium hydroxide, followed by aluminium foil. Heat the mixture gently	effervescence colourless, pungent gas produced gas turned moist red litmus paper blue

 

TEST FOR GASES

 

Gas	Test	Observations
Ammonia (NH3)	Place moist red litmus paper near the mouth of test tube	Gas turned moist red litmus paper blue
Carbon dioxide (CO2)	Bubble gas into limewater using a delivery tube	Gas formed white ppt with limewater
Chlorine (Cl2)	Place moist blue litmus paper near the mouth of test tube	Gas turned moist blue litmus paper red and then bleached it
Hydrogen (H2)	Place a lighted splint near the mouth of the test tube	Gas extinguished lighted splint with a "pop" sound
Oxygen (O2)	Place a glowing splint inside the test tube	Gas relighted a glowing splint
Sulfur dioxide (SO2)	Bubble gas into acidified potassium manganate (VII) using a delivery tube	Gas turned potassium manganate (VII) from purple to colourless