Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Chemistry (Helena) > Electrolysis > Flashcards

Electrolysis Flashcards

You may prefer our related Brainscape-certified flashcards:
Periodic Table flashcards Chemistry 101 flashcards AP® Chemistry flashcards Organic Chemistry 101 flashcards
1
Q

Definition of electrolysis

A

The passage of electricity through a chemical substance causing a chemical change and the formation of new substances at the electrodes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

for the bulb to light there must be?

A

a complete circuit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Ionic substances dissolve in water to form what?

A

An aqueous solution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

The ions in the ionic substance become what>

A

Mobile

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

if the aqueous solution is connected in a circuit what will happen?

A

an electric current will flow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

The aqueous solution is an example of what?

A

An electrolyte

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Give three examples of an aqueous solution

A

Sodium chloride solution
dilute sulphuric acid
copper sulphate solution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

electrolysis of sodium chloride solution observation at the anode (positive electrode)

A

fizzing and chlorine smell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

electrolysis of sodium chloride solution observation at the cathode (negative electode

A

hydrogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

half equation for oxygen

A

4OH(-) - 4E- = 02 + 2H(2)0

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

half equation for hydrogen

A

2H+ (+) 2E- = H2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the ‘rules’ for the anode (positive electrode)

A
  • halide ions always lose their electrons before hydroxide ions
  • hydroxide ions will lose their electrons before sulphate or nitrate ect
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what are the ‘rules’ at the cathode?

A

metal ions below hydrogen in the reactivity series always gains electrons before H+ ions
-H+ ions always gain electrons before metal ions that are above it in the reactivity series

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Definition of the electrolysis of brine

A

a very important electrolysis of concentrated sodium chloride solution used in the industry

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what does the electrolysis of brine produce?

A
  • Chlorine Gas
  • Hydrogen Gas
  • Sodium Hydroxide Solution
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the ions present in brine

A

Sodium
chlorine
hydroxide
hydrogen

17
Q

whats happens when an electrical current passes through brine at the cathode (-)

A

sodium and hydrogen ions move to the cathode
-H+ ions gain electrons and H+ gas is released
Na+ ions remain in solution

18
Q

What happens when an electrical current passes through brine at the Anode (+)

A
  • chloride and hydroxide ions move to the anode
  • chloride ions lose electrons and chlorine gas is released
  • hydroxide ions remain in solution
19
Q

What is made in the electrolysis of brine and at which electrode or other>

A
  • Hydrogen gas at the cathode
  • Chlorine Gas at the anode
  • sodium hydroxide solution left in the container
20
Q

What is Hyrogen Gas used for?

A
  • harden veg oil into margarine

- make hydrochloric acid for use in pharmacy industry

21
Q

What is chlorine gas used for?

A

(poisonous) -to kill bacteria in drinking water and pools
- to make bleach + pvc/plastics
- to make disinfectant

22
Q

what is sodium hydroxide solution used for?

A
  • soap
  • paper
  • bleach
23
Q

What is the test for hydrogen?

A

insert a lighted splint
gas burns with a pop
HAZARD- in air a spark causes explosion

24
Q

test for oxygen?

A

insert a glowing splint

the splint relights

25
Q

Test for carbon dioxide

A
  • bubble the gas through limewater

- the limiter turns milky

26
Q

test for chlorine

A
  • put damp BLUE litmus paper in the gas

- the litmus turns pink and then BLEACHES

27
Q

test for Ammonia

A

put red litmus in the gas
-the litmus turns blue the gas is alkaline
HAZARD= alkaline very soluble in water danger of suck back

28
Q

Hydrogen chloride test

A

put the gas ned to a bottle of ammonia solution

the gas gives dense white fumes of ammonium chloride

29
Q

test for water x2

A

add to anhydrous copper sulphate(white) add to blue cobalt chloride paper
-anyhydrous copper sulphate turns blue
blue cobalt chloride paper turns pink

30
Q

Test for pure water

A

boils at 100C

freezes at 0C

31
Q

test for Alkenes C=C double bonds (unsaturated hydrocarbons)

A

shake with bromine water

-bromine water decolourises turns from yellow/brown to colourless

32
Q

definition of an electrolyte

A

a liquid or gel which contains ions and can be decomposed by electrolysis, e.g. that present in a battery.

33
Q

definition of conductor

A

a metal that conducts electricity when it is solid as it does not have mobile ions

34
Q

In a circuit which way do the electrons go

A

negative to positive

35
Q

Why does solid Lead (II) not undergo electrolysis

A

It doesn’t have mobile ions

36
Q

Describe what you would observe in the electrolysis of lead (II)

A

lead- a shiny substance would form at the cathode and bromine gas and fizzing would be given off at the anode

Chemistry (Helena) (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions