Analysis

Question 1

How do you test for Aluminium?

Answer 1

Aqueous sodium hydroxide: WHITE precipitate forms which is SOLUBLE, in excess giving a COLOURLESS solution

Aqueous Ammonia: WHITE precipitate forms which is INSOLUBLE in excess

Question 2

How do you test for Zinc?

Answer 2

Aqueous sodium hydroxide: WHITE precipitate forms which is SOLUBLE, in excess giving a COLOURLESS solution

Aqueous Ammonia: WHITE precipitate forms which is SOLUBLE in excess giving a colorless solution

Question 3

How do you test for Calcium?

Answer 3

Aqueous sodium hydroxide: WHITE precipitate forms, which is INSOLUBLE in excess

Aqueous Ammonia: NO precipitate or very slight white precipitate, insoluble in excess

Question 4

How do you test for Chromium?

Answer 4

Aqueous sodium hydroxide: GREEN precipitate forms, which is SOLUBLE in excess. ( solution )

Aqueous Ammonia: GREY-GREEN precipitate forms, which is INSOLUBLE in excess

Question 5

How do you test for Copper?

Answer 5

Aqueous sodium hydroxide: LIGHT BLUE precipitate forms which is INSOLUBLE in excess

Aqueous Ammonia: LIGHT BLUE precipitate forms, which is SOLUBLE in excess giving a DARK BLUE solution

Question 6

How do you test for Iron(II)?

Answer 6

Aqueous sodium hydroxide: GREEN precipitate forms, which is INSOLUBLE in excess. On standing for 5 minutes the surface turns RED-BROWN

Aqueous Ammonia: GREEN precipitate forms, which is INSOLUBLE in excess. On standing for 5 minutes the surface turns RED-BROWN as Fe3+ is formed

Question 7

How do you test for Iron(III)?

Answer 7

Aqueous sodium hydroxide: RED-BROWN precipitate forms which is INSOLUBLE in excess

Aqueous Ammonia: RED-BROWN precipitate forms which is INSOLUBLE in excess

Question 8

How do you test for Ammonium?

Answer 8

Aqueous sodium hydroxide: AMMONIA GAS is produced on warming which turns dam red litmus blue
( No precipitate as its soluble )

Question 9

How do you test for metal ions?

Lithium, Sodium, Potassium, and Copper(II)

Answer 9

Lithium - Red flame color
Sodium - Yellow flame color
Potassium - Lilac flame colour
Copper (II) - Blue/green flame colour

Question 10

How do you test for Carbonate? (CO3)

Answer 10

Add dilute nitric acid (gas produced)

Result: Bubble gas evolved through limewater, limewater changes from colourless to white precipitate (Carbon dioxide)

Question 11

How do you test for Chloride (Cl), Bromide (Br), and Iodide (I)?

Answer 11

Acidify with dilute nitric acid, then add aqueous silver nitrate
Result:
Chloride: White precipitate (Silver(I) chloride)
Bromide: Cream precipitate (Silver(I) bromide)
Iodide: Yellow precipitate (Silver(I) Iodide)

Question 12

How do you test for Nitrate?

Answer 12

add aqueous sodium hydroxide then aluminum foil; war carefully (gas produced)
Result: Gas produced which turns damp red litmus paper blue (ammonia)

Question 13

How do you test for sulfate?

Answer 13

Acidify with dilute nitric acid, then add aqueous barium nitrate aqueous barium chloride
Result: white precipitate (barium sulfate)

Question 14

How do you test for sulfite?

Answer 14

Add dilute hydrochloric acid, warm gently (gas produced)

Result: Gas produced which will turn acidified potassium manganate (VII) from purple to colourless (sulfur dioxide)

Question 15

How do you test for Carbon dioxide?

Answer 15

Bubble gas through limewater, The limewater will turn from colourless to white precipitate

Question 16

How do you test for Chlorine?

Answer 16

Damp red, or blue litmus paper. It will be bleached and turn white

Question 17

How do you test for Hydrogen gas?

Answer 17

Lighted splint, There will be a ‘squeaky pop’

Question 18

How do you test for Oxygen?

Answer 18

Glowing splint, It will relight

Question 19

How do you test for sulfur dioxide?

Answer 19

Acidified potassium manganate, Paper change from purple to colourless