Tests for Gases, Anions and Cations

Question 1

What are the four common gas tests?

Answer 1

Hydrogen, Carbon Dioxide, Oxygen, Chlorine

Question 2

Hydrogen Test

Answer 2

Squeaky Pop Test
Put a lit splint in the area and if there is hydrogen there will be a pop

Question 3

Carbon dioxide test

Answer 3

Cloudy limewater
Bubbling Carbon dioxide through will cause limewater o turn cloudy

Question 4

Oxygen tests

Answer 4

A glowing splint will relight if oxygen is present

Question 5

Chlorine

Answer 5

Bleaches litmus paper

Question 6

What do tests for anions often give?

Answer 6

Precipitates

Question 7

What do dilute acids detect?

Answer 7

Carbonates

Question 8

Test for carbonates

Answer 8

Add a dilute acid to the sample and connect the test tube to a test tube containing limewater. If positive the limewater will go cloudys

Question 9

What is a carbonate

Answer 9

Substance that contains CO3 2- ions

Question 10

What is a sulphate

Answer 10

SO4 2-

Question 11

Test for sulphates

Answer 11

Add hydrochloric acid and barium chloride solution to the sample
If positive a white precipitate will form

Question 12

Test for hallides

Answer 12

Add nitric acid and silver nitrate solution to solution which will form a precipitate if positive (white, cream or yellow)

Question 13

Positive Chloride test

Answer 13

White precipitate

Question 14

Positive bromide test

Answer 14

Cream precipitate

Question 15

Positive iodide test

Answer 15

Yellow

Question 16

Test for metal ions

Answer 16

Flame test

Question 17

Lithium Flame

Answer 17

Crimson flame

Question 18

Sodium Flame

Answer 18

Yellow flame

Question 19

Potassium Flame

Answer 19

Lilac flame

Question 20

Calcium Flame

Answer 20

Orange-Red flame

Question 21

Copper flame

Answer 21

Green flame

Question 22

Metals+NaOH =?

Answer 22

Coloured precipitate

Question 23

Calcium precipitate colour

Answer 23

white

Question 24

Copper precipitate colour

Answer 24

blue

Question 25

Iron (II) precipitate colour

Answer 25

Green

Question 26

Iron (III) precipitate colour

Answer 26

Brown

Question 27

Aluminium precipitate colour

Answer 27

White but redissolves

Question 28

Magnesium precipitate colour

Answer 28

White

Question 29

What is Flame Emission Spectroscopy?

Answer 29

When a sample is placed in a flame and electrons transfer light energy, which passes through a spectroscope. This detects different wavelengths of light. As no two ions contain the same charge and electron arrangement, they produce unique wavelength patterns

Question 30

Why use Flame Emission SPectroscopy?

Answer 30

Can detect mixtures Very sensitive Very fast Accurate Uses small samples

Question 31

Acromyn to remember flame tests

Answer 31

Luke Cuthburt says yes please like comment or call gary