Tests

Question 1

Test for CO2

Answer 1

CO2 +Ca(OH)2 -> CaCO3 +H2O

-Lime water goes cloudy

Question 2

Test for sulfate ions

Answer 2

• Barium chloride/nitrate
• add Nitric acid too
• Sulfate ions in the solution would react with the barium
• This forms barium sulfate which can be seen as a
• WHITE PRECIPITATE forms

Question 3

Test for ammonium ions

Answer 3

-Add NaOH solution and warm it
(NH3 + OH- ➝ NH3 + H2O)
-Ammonia is released so use DAMP RED litmus paper which turns blue
-Or use HCL which forms ammonium chloride (white misty fumes)

Question 4

Test for ammonia

Answer 4

-Damp Red litmus paper turns blue

Question 5

Test for chlorine

Answer 5

-damp blue Litmus paper bleached white

Question 6

Test to identify aldehydes and ketones

Answer 6

• 2,4 -dinitrophenylhydrazine

(+) bright orange precipitate

Question 7

Test to identify the presence of a CH3CO group

Answer 7

CHI3 Trichloromethane

(+) yellow precipitate

Question 8

Aldehyde distinction

Answer 8

-Tollen’s reagent

(+)Silver mirror

Question 9

Test for aldehyde with acidified potassium dichromate (VI)

Answer 9

-heat under reflux orange -> green

Question 10

Aldehyde distinction (Fehling’s solution)

Answer 10

Deep blue -> red precipitate

Question 11

Aldehyde Benedict’s

Answer 11

Blue-> red precipitate