Flame tests

Question 1

Describe the flame test

Answer 1

1. Clean nichrome wire with concentrated HCl
2. Place over blue flame to dry until no colour is present
3. dip into HCL again
4. scoop some of the soild(powder needed)
5. place at the edge of the flame and observe colour change
6. repeat with different solids

Question 2

What is the result for copper in the flame test

Answer 2

Blue

Question 3

What is the result for Lithium in the flame test

Answer 3

Crimson

Question 4

What is the result for Calcium in the flame test

Answer 4

Brick red/ Orange

Question 5

What is the result for Potassium in the flame test

Answer 5

Lilac

Question 6

What is the result for Sodium in the flame test

Answer 6

Yellow/Orange

Question 7

What is a percipitate

Answer 7

It is a solid formed in a reaction (Insoluble)

Question 8

what does copper (cu3+ ) form in precipitation with sodium hydroxide

Answer 8

Blue precipitate

Question 9

what does Aluminium(Al3+) form in precipitation with sodium hydroxide

Answer 9

White precipitate

Question 10

what does Calcium(ca2+ ) form in precipitation with sodium hydroxide

Answer 10

White precipitate

Question 11

what does Iron 2 (Fe2+ ) form in precipitation with sodium hydroxide

Answer 11

Green precipitate

Question 12

what does Iron3 (Fe3+ ) form in precipitation with sodium hydroxide

Answer 12

Brown precpitate

Question 13

What happens it Aluminium ions in excess Sodium Hydroxide

Answer 13

Dissolves in excess

Question 14

What is the test for Carbonates

Answer 14

Dilute acid and limewater

Question 15

What is the result it carbonates are present and why?

Answer 15

Colourless to cloudy ( Carbon dioxide reacts with limewater for observation)

Question 16

What is the test for halides

Answer 16

Adding nitric acid and silver nitrate

Question 17

Why is nitric acid added for the test if halides

Answer 17

To remove any impurities (e.g, OH-)

Question 18

What is precipitate of Chlorine

Answer 18

White precipitate

Question 19

What is the precipitate for Bromine

Answer 19

Cream precipitate

Question 20

What is the precipitate of Iodine

Answer 20

Yellow precipitate

Question 21

What is the precipitate of Flourine
and what mistake can be done with fluorine

Answer 21

Colourless solution ( If impurities aren’t removed it will form a white precipitate and could be mistaken for chlorine)

Question 22

What is the test for sulphates

Answer 22

Adding Hydrochloric acid and Barium chloride

Question 23

What is precipitate if sulphates are present

Answer 23

White precipitate

Question 24

How do you test for Carbon dioxide

Answer 24

Bubble co2 gas in limewater

Question 25

What is the test for chlorine

Answer 25

Place a damp blue litmus paper into a test tube with chlorine gas

Question 26

What is the test for Hydrogen

Answer 26

Place a lit splint into a test tube with hydrogen gas

Question 27

What is the test for oxygen

Answer 27

Place a glowing splint into a test tube containing oxygen gas

Question 28

What is the result for hydrogen test

Answer 28

Squeaky pop sound

Question 29

What is the result for a chlorine test

Answer 29

Bleaches damp blue litmus paper

Question 30

What is the result for carbon dioxide test

Answer 30

Turns limewater cloudy

Question 31

What is the result for the oxygen gas test

Answer 31

Relights glowing splint