Chapter 22: Chemical Analysis

Question 1

What is the observed flame colour for lithium?

Answer 1

Red

Question 2

What is the observed flame colour for sodium?

Answer 2

Yellow

Question 3

What is the observed flame colour for potassium?

Answer 3

Lilac

Question 4

What is the observed flame colour for calcium?

Answer 4

Orange-red

Question 5

What is the observed flame colour for barium?

Answer 5

Light green

Question 6

What is the observed flame colour for copper(II)?

Answer 6

Blue-green

Question 7

What is the precipitate’s colour when NaOH(aq) is added with aluminium AND what happens when excess NaOH(aq) is added

Answer 7

White precipitate
Redissolves when excess NaOH is added to give a colourless solution

Question 8

What is the precipitate’s colour when NaOH(aq) is added with calcium AND what happens when excess NaOH(aq) is added

Answer 8

White precipitate
Insoluble in excess NaOH

Question 9

What is the precipitate’s colour when NaOH(aq) is added with chromium(III) AND what happens when excess NaOH(aq) is added

Answer 9

Green precipitate
Redissolves when excess NaOH is added

Question 10

What is the precipitate’s colour when NaOH(aq) is added with copper(II) AND what happens when excess NaOH(aq) is added

Answer 10

Light blue precipitate
Insoluble in excess NaOH

Question 11

What is the precipitate’s colour when NaOH(aq) is added with iron(II) AND what happens when excess NaOH(aq) is added

Answer 11

Green precipitate
Insoluble in excess NaOH

+Starts to turn brown near surface if left to stand

Question 12

What is the precipitate’s colour when NaOH(aq) is added with iron(III) AND what happens when excess NaOH(aq) is added

Answer 12

Red-brown precipitate
Insoluble in excess NaOH

Question 13

What is the precipitate’s colour when NaOH(aq) is added with zinc AND what happens when excess NaOH(aq) is added

Answer 13

White precipitate
Redissolves when excess NaOH is added

Question 14

What is the precipitate’s colour when NaOH(aq) is added with ammonium AND what happens when excess NaOH(aq) is added

Answer 14

No precipitate is formed BUT it produces ammonia on warming

Question 15

What is the precipitate’s colour when NH3(aq) is added with aluminum AND what happens when excess NH3(aq) is added

Answer 15

White precipitate
Insoluble in excess NH3

Question 16

What is the precipitate’s colour when NH3(aq) is added with calcium AND what happens when excess NH3(aq) is added

Answer 16

No precipitate
OR
Slightly white precipitate

Question 17

What is the precipitate’s colour when NH3(aq) is added with chromium(III) AND what happens when excess NH3(aq) is added

Answer 17

Green precipitate
Insoluble in excess NH3

Question 18

What is the precipitate’s colour when NH3(aq) is added with copper(II) AND what happens when excess NH3(aq) is added

Answer 18

Light blue precipitate
Soluble in excess NH3 producing a dark blue solution

Question 19

What is the precipitate’s colour when NH3(aq) is added with iron(II) AND what happens when excess NH3(aq) is added

Answer 19

Green precipitate
Insoluble in excess NH3 but turns brown near the surface if left to stand

Question 20

What is the precipitate’s colour when NH3(aq) is added with iron(III) AND what happens when excess NH3(aq) is added

Answer 20

Red-brown precipitate
Insoluble in excess NH3

Question 21

What is the precipitate’s colour when NH3(aq) is added with zinc AND what happens when excess NH3(aq) is added

Answer 21

White precipitate
Redissolves in excess NH3 to give a colourless solution

Question 22

What is the result of the test where dilute HCL is added to a carbonate

Answer 22

-Effervescence
-CO2 produced

Question 23

What is the precipitate AND its colour in the reaction of chloride with dilute nitric acid, and then aqueous silver nitrate is added

Answer 23

Silver chloride
White

Question 24

What is the precipitate AND its colour in the reaction of bromide with dilute nitric acid, and then aqueous silver nitrate is added

Answer 24

Silver bromide
Cream

Question 25

What is the precipitate AND its colour in the reaction of Iodide with dilute nitric acid, and then aqueous silver nitrate is added

Answer 25

Silver iodide Yellow

Question 26

What is the precipitate AND its colour in the reaction of sulfate with dilute nitric acid, and then aqueous barium nitrate is added

Answer 26

Barium sulfate White

Question 27

What happens to aqueous potassium manganate(VII) when reacting with the product of a sulfite reacting to HCl

Answer 27

It decolourises(Purple to colourless)

Question 28

What gas is given off when nitrate reacts with aqueous sodium hydroxide, then aluminium foil is added and warmed carefully

Answer 28

Ammonia gas is given off

Question 29

What is the test for hydrogen gas?

Answer 29

Squeaky pop test

Question 30

What is the test for oxygen gas?

Answer 30

Relights a glowing splint

Question 31

What is the test for carbon dioxide gas?

Answer 31

Limewater turns from colourless to milky/cloudy

Question 32

What is the test for chlorine gas?

Answer 32

Bleaches damp blue litmus paper

Question 33

What is the test for ammonia gas?

Answer 33

Turns damp red litmus paper blue

Question 34

What is the test for sulfur dioxide gas?

Answer 34

Decolourises potassium manganate(VII)