Tests For Anions And Cations (2)

Question 1

To find Cations you can use _________ tests

Answer 1

Flame

Question 2

Lithium burns with a ______ flame

Answer 2

Red

Question 3

Sodium burns with a _________-_________ flame

Answer 3

Yellow-orange

Question 4

Potassium burns with a _________ flame

Answer 4

Lilac

Question 5

Calcium burns with a ________ _____ flame

Answer 5

Brick red

Question 6

To do a flame test you need to clean the wire by dipping it in some dilute __________________ ______ and holding it in a flame. Then when it shows no ___________, it is clean and you can dip it into the sample (E.g Lithium) and it will show a colour

Answer 6

Hydrochloric acid

Colour

Question 7

Some metals form a coloured precipitate with ________

Answer 7

NaOH

Sodium Hydroxide

Question 8

Many metal hydroxides are insoluble and precipitate out of solution when formed. Some of these hydroxides have a characteristic colour. So in this test you add a few drops of ___________ _______________ solution to the solution of your unknown compound - in the hope of forming an insoluble _____________. If you get a colour then you can tell which metal was in the compound

Answer 8

Sodium hydroxide

Insoluble hydroxide

Question 9

If the colour of the precipitate is blue then what is the metal ion

Answer 9

Copper (||)

Question 10

If the colour of the precipitate is sludgy green then what is the metal ion

Answer 10

Iron (||) 2

Question 11

If the colour of the precipitate is reddish brown then what is the metal ion

Answer 11

Iron (|||) 3

Question 12

Equation/ionic reaction of cu2+ and NaOH

Answer 12

Cu2+ (aq) + 2OH- (aq) → Cu(OH)2 (s)

Question 13

Equation/ionic reaction of Fe2+ and NaOH

Answer 13

Fe2+ (aq)+ 2OH- (aq) → Fe(OH)2 (s)

Question 14

Equation/ionic reaction of Fe3+ and NaOH

Answer 14

Fe3+ (aq) + 3OH- (aq) → Fe(OH)3 (s)

Question 15

An _____________ compound + NaOH gives off Ammonia which does not smell good

Answer 15

Ammonium

Question 16

How to test for ammonia gas

Answer 16

By using a damp piece of red litmus paper that will turn blue if ammonia is present

Question 17

Add some sodium hydroxide to your mystery substance in a test tube If there’s ammonia given off this means there are ______________ ions in your mystery substance.

Answer 17

Ammonium

Question 18

Hydrochloric acid can help detect ____________ which are anions

Answer 18

Carbonates

Question 19

To test for carbonates, add dilute hydrochloric acid (HCl) to your test sample. If carbonates are present then __________ __________ will be released

Answer 19

Carbon dioxide

Question 20

Test for carbon dioxide:

Answer 20

Limewater will go milky

Question 21

How do you test for sulfates? What appears to show that the original compound was a sulfate

Answer 21

Hydrochloric acid followed by barium chloride

White precipitate

Question 22

Why is hydrochloric acid added to the ‘test for sulfates’ experiment

Answer 22

To clean out any carbonate or sulfite ions

Question 23

To test for halides (chloride, bromide or iodide ions,) add dilute __________ acid, followed by ____________ ____________ solution

Answer 23

Nitric

Silver nitrate solution

Question 24

What do you use to test for chloride ions and what will be formed? A chloride ion gives a __________ precipitate of silver chloride

Answer 24

Nitric acid followed by silver nitrate solution

White

Question 25

What do you use to test for bromide ions and what will be formed? A bromide ion gives a __________ precipitate of silver bromide

Answer 25

Nitric acid followed by silver nitrate solution | Cream

Question 26

What do you use to test for iodide ions and what will be formed? An iodide ion gives a ___________ precipitate of silver iodide

Answer 26

Nitric acid followed by silver nitrate solution | Yellow

Question 27

Why is nitric acid added to the 'test for halides' experiment

Answer 27

To clean out any carbonates or sulfite ions

Question 28

What are flame tests used to identify

Answer 28

Metal ions (Lithium, sodium, potassium, calcium)

Question 29

What is sodium hydroxide used to identify

Answer 29

Metal ions (Copper and iron)

Question 30

How can you use NaOH to test for ammonia

Answer 30

After adding the NaOH, check to see if it turns damp red litmus paper blue

Question 31

What is hydrochloric acid used to test for

Answer 31

Carbonates

Question 32

What is HCI and Barium chloride used to test for

Answer 32

Sulfates

Question 33

What can you test for by adding dilute nitric acid followed by silver nitrate solutions (AgNO3)

Answer 33

Halides

Question 34

How to test for Lithium, sodium, potassium, calcium

Answer 34

Flame tests

Question 35

How to test for Copper and iron

Answer 35

Add sodium hydroxide (NaOH) and see the colour of precipitate

Question 36

How to test for ammonia

Answer 36

Add sodium hydroxide (NaOH) and then see if it turns damp red litmus paper blue

Question 37

How to test for carbonates

Answer 37

Add dilute hydrochloric acid to your test sample

Question 38

How to test for sulfates

Answer 38

Dilute HCI followed by barium chloride solution

Question 39

How to test for halides

Answer 39

Nitric acid (HNO3) followed by silver nitrate solution

Question 40

Hydrochloric acid and nitric acid are both used to clean out any traces of carbonates or sulfite ions - which is used for which experiment?

Answer 40

Hydrochloric acid is used to test for sulfates | Nitric acid is used to test for halides