Electrolysis Flashcards Preview

GCSE Chemistry > Electrolysis > Flashcards

Flashcards in Electrolysis Deck (20):
1

What is electric current ?

The flow of electrons or ions

2

When do ionic compounds conduct electricity?

When molten or in solution

3

Why do they only conduct electricity when molten or in solution?

Because when they are solid the ions aren't free to move around. But when they are dissolved the ions are free to move in the solution and so they conduct electricity

4

What is electrolysis ?

The breakdown of substances using electricity

5

What is an electrolyte?

Is a molten substance or solution that conducts electricity and is decomposed

6

What is the positive electrode called?

Anode

7

What is the negative electrode called?

Cathode

8

What are positively charged ions called?

Cations

9

What are negatively charged ions called?

Anions

10

In aqueous solutions, apart from the ions in the ionic compound ,what other ions are always present?

H+ and OH-

11

At the cathode when is hydrogen produced?

When the metal ions are more reactive than the H+ ions

12

At the cathode when is hydrogen not produced ?

If the metal ions are less reactive than the H+ ions OR if the solution is molten

13

At the anode what is produced ?

Cl-, I-, Br- or O2 2-

14

How do you work out charge?

Charge (C) = current (A) x time (s) ( Q = IT )

15

How big is 1 faraday?

1 faraday = 96,500 coulombs

16

What is the chemical name of brine?

Sodium chloride solution

17

What are the 3 useful products of the electrolysis of brine?

Hydrogen
Chlorine
Sodium

18

What is chlorine used for ?

To sterilise water supplies and make bleach

19

What is hydrogen used for ?

Manufacture of ammonia & manufacture of margarine

20

What is Sodium Hydroxide used for?

Manufacture of bleach and soap