Electrolysis recap quiz

Substances that let electricity pass through them are called _________?

Metals can conduct electricity because......

• the ions are free to move

• none of the electrons are free to move

• there are free electrons to move when voltage is applied

Answer explanation

free ions are only in liquid/ electrolyte. free electrons is in the wire

Sulfur does not conduct electricity because .......

• the ions are not free to move.

• because none of the electrons are free to move

Answer explanation

sulfur is a non-metal in the period table. Hence no free moving electrons to allow it to flow through to the wire.

Define electrolyte by completing the following sentence with two words.

Electrolyte is a liquid that __________ ____________ .

Answer explanation

a solid ionic compound like salt is an electrolyte as it can conduct electricity. Remember the sodium video? But only in molten condition as there are free ions to move around.

Define electrolysis by completing the following sentence using 3 words.

Electrolysis is the breakdown of ________ substance when ________ or in solution by passage of _____________ .

[write your answer as ______,______,________]

Answer explanation

Remember anytime electricity is passed through a substances that conduct electricity it will decompose and turn into a liquid. Decompose mean the state of change from solid to liquid state.

Which of the following is what makes up an electrolysis cell. You may select more than one options.

• electrolyte

• anode

• cathode

• battery/power supply

Answer explanation

It is important that you practice drawing these cells and label them.

I carry current (e^-) in and out of the liquid during electrolysis.

Who am I?

Answer explanation

I am made up of anode and cathode. Do you remember who is +ve and -ve?

How can you tell which electrode is +ve?

• it is connected to the -ve terminal of the battery

• it is connected to the +ve terminal of the battery

Answer explanation

You can also remember add (+) as +ve or the anode.

A molten ionic compound is made up of a metal and a non-metal.

• True

• False

Answer explanation

NaCl is ionic compound. Na⁺ is a metal. Cl^- is a non metal.

Sodium or Na in molten state becomes an ion Na⁺. Is Na⁺ a cation or anion.

• cation

• anion

Answer explanation

an element with +ve charged ion is a cation.