Chemistry 8 -Electrolysis

Question 1

Lithium ions flame colour?

Answer 1

Crimson Flame

Question 2

Sodium ions flame colour?

Answer 2

Yellow flame

Question 3

Potassium ions flame colour?

Answer 3

Liliac Flame

Question 4

Calcium ions flame colour?

Answer 4

Red flame

Question 5

Barium ions flame colour?

Answer 5

Green flame

Question 6

What colour does chlorine turn damp litmus paper?

Answer 6

bleaches it turning it white

Question 7

How can you test for oxygen

Answer 7

it relights a glowing splint

Question 8

How can you test for hydrogen?

Answer 8

squeaky pop

Question 9

Calcium Hydroxide forms when calcium mixes with what?

What colour does it go?

Answer 9

NaOH

White precipitate

Question 10

Copper (2) when mixed with NaOH turns what colour?

What does it form?

Answer 10

Blue

Copper hydroxide

Question 11

Iron (2) when mixed with NaOH turns what colour?

What does it form?

Answer 11

Green

Iron Hydroxide

Question 12

Iron (3) when mixed with NaOH turns what colour?

What does it form?

Answer 12

Brown

Iron Hydroxide

Question 13

Aluminium mixed with NaOH turns what colour?

What does it form?

Answer 13

Colourless solution

ALuminium hydroxide

Question 14

Magnesium mixed with NaOH turns what colour?

WHat does it form?

Answer 14

White

Magnesium Hydroxide

Question 15

Acid + Carbonates =

Answer 15

Salt + water + CO2

Question 16

Testing for carbonates can be done how?

Answer 16

Limewater turning cloudy

Question 17

GIve 3 examples of halide ions

Answer 17

Chloride / bromide / iodide

Question 18

How can you test for Halides?

Answer 18

Add dilute nitric acid

then Silver Nitrate Solution

Question 19

With the Halide test, what colour does Chloride ions go?

Whats formed?

Answer 19

White Precipitate

Silver Chloride

Question 20

With the Halide test, what colour does Bromide ions go?

Whats formed?

Answer 20

Cream Precipitate

Silver Bromide

Question 21

With the Halide test, what colour does Iodide ions go?

WHats formed?

Answer 21

yellow Precipitate

Silver Iodide

Question 22

How do we test for Sulphate ions?

Answer 22

add Dilute HCl

Then Barium Chloride Solution

Question 23

Whats formed if sulphate ions are present?

Answer 23

Barium Sulphate

WHite precipitate

Question 24

In the Mobile Phase, what can molecules do?

What generally are mobile phase?

Answer 24

They can move

Liquid/gas

Question 25

In the Stationary Phase, what can molecules not do? What generally are mobile phase?

Answer 25

They cant move Solid or a thick liquid

Question 26

In paper chromotography, what is the stationary phase? " what is the mobile phase?

Answer 26

The paper Solvent (Ethanol/water)

Question 27

The amount of time spent in each phase, depends on what two things?

Answer 27

How soluble they are in the solvent How attracted they are to the paper

Question 28

Molecules with a .......... in the solvent , and are less ....... to the paper, will spend ......... in the mobile phase. what does this cause

Answer 28

Higher solubility , attracted , more time They move up the paper more

Question 29

in Thin Layer Chromatography, what is the stationary phase?

Answer 29

Silica gel

Question 30

The result of chromotagraphy analysis, is called what?

Answer 30

Chromatogram

Question 31

What is the Rf?

Answer 31

Ratio between the distance travelled by the dissolved substance and the distance travelled by the solvent

Question 32

what can standard reference materials (SRM) do?

Answer 32

Check identities of substances

Question 33

In titrations, Phenolphathalein is what colour in acid? WHat colour in alkali?

Answer 33

Pink in Alkali Colourless in acids

Question 34

In titrations, Methyl Orange is what colour in acid? What colour in alkali?

Answer 34

Yellow in alkali Red in Acids

Question 35

Number of moles =

Answer 35

Concentration x Volume

Question 36

Mass in grams

Answer 36

Moles x RFM

Question 37

% purity =

Answer 37

Calculated mass of substance ---------------------------------------------- x100 Mass of impure substance at start

Question 38

In electrolysis, what need substance needs to be present?

Answer 38

Ionic substance thats molten/solution

Question 39

Electrolytes do what do electricity? What do they contain

Answer 39

conduct electricity Free ions

Question 40

Electrons are taken away from where and given to where?

Answer 40

Taken AWAY from POSITIVE electrode GIVEN to other ions at the NEGATIVE electrode

Question 41

Oxidation is a gain of what?

Answer 41

Oxygen

Question 42

Reduction is a loss of what?

Answer 42

Oxygen

Question 43

In the Molten ionic substance, where does the positive ions go to?

Answer 43

Negative electrode They accept electrons to become an atom

Question 44

When metal ions and H+ ions (From water) are present, what happens when metals that are MORE REACTIVE than hydrogen go to become? What happens when they are LESS REACTIVE

Answer 44

they stay as ions if they are more reactive (Hydrogen produced) They become atoms if they are less reactive (H+ remain H+ ions)

Question 45

When halide ions and OH- ions (from water) are present, , what happens to the halide ions? What happens when halide are not present

Answer 45

They form the atom (chlorine, bromine, iodine) O2 will form

Question 46

what metals are less reactive than hydrogen?

Answer 46

copper / silver /gold / platinum

Question 47

Draw out what the electrolysis of Sodium Chloride and the products formed and HCl

Answer 47

=

Question 48

When electroplating, the object being plated is always the

Answer 48

Cathode

Question 49

What can a seperating funnel do?

Answer 49

Separate immiscible liquids

Question 50

What can fractional distillation separate?

Answer 50

Miscible liquids

Question 51

How can you separate soluble/insoluble solids?

Answer 51

Dissolving Filtration Cystallisation