Electrolysis

Copper and hydrogen can each be formed by electrolysis. At which electrodes are these elements formed?

• A

• B

• C

• D

Tags

NGSS.HS-PS1-1

Which substance does NOT produce a gas at both electrodes during electrolysis?

• concentrated aqueous sodium chloride

• concentrated hydrochloric acid

• dilute sulfuric acid

• molten lead(II) bromide

The apparatus used for electrolysis is shown.

Which statement is correct?

• Copper forms at the anode in some electrolysis reactions.

• Hydrogen forms at the cathode in some electrolysis reactions.

• Oxygen forms at the cathode in some electrolysis reactions.

• The negative electrode is called the anode.

Three electrolysis cells are set up. Each cell has inert electrodes.

The electrolytes are listed below.

cell 1 aqueous sodium chloride

cell 2 dilute sulfuric acid

cell 3 molten lead(II) bromide

In which of these cells is a gas formed at both electrodes?

• 1 and 2

• 1 and 3

• 2 only

• 3 only

What is the main process occurring in an electrolytic cell?

• Chemical energy is converted into electrical energy.

• Electrical energy is converted into chemical energy.

• Thermal energy is converted into chemical energy.

• Mechanical energy is converted into electrical energy.

What type of compound can undergo electrolysis?

• Metallic

• Giant covalent

• Simple covalent

• Ionic

What is the main difference between galvanic cells and electrolytic cells?

• Galvanic cells require an external power source, while electrolytic cells do not.

• Electrolytic cells require an external power source, while galvanic cells do not.

• Galvanic cells can only operate under acidic conditions.

• Electrolytic cells can only operate under basic conditions.

The diagram shows apparatus for plating a spoon with silver.

Which statement is not correct?

• Silver would stick to the spoon because it is a very reactive metal.

• The electrolyte would be a silver salt dissolved in water.

• The metal electrode would be made from silver..

• The spoon would be connected to the negative terminal of the power supply.

Tags

NGSS.HS-PS3-5

What is the name given to the solution that is being electrolysed?

• Salt solution

• Electric solution

• Mineral solution

• Electrolyte

Explain why the electrolyte has to be a liquid.

• So the ions can move

• So the electrons can move

• So that it doesn't get too hot

• So the fish are ok