Understanding Electrolysis

What is electrolysis used for?

• To split compounds into their elements

• To combine elements into compounds

• To decrease the reactivity of metals

• To increase the electrical conductivity of a solution

What must happen to the ions in an electrolyte for electrolysis to work?

• They must be free to move around

• They must be positively charged only

• They must be stationary

• They must be in a gaseous state

How can insoluble compounds like metal oxides be prepared for electrolysis?

• By melting them to make them a molten liquid

• By cooling them to a solid state

• By passing an electric current through them

• By dissolving them in water

What are the charges of the electrodes in an electrolysis setup?

• Variable

• Neutral

• Positive

• Negative

Which ions will the negative electrode attract?

• Negative ions only

• Positive ions only

• Both positive and negative ions

• No ions

What determines which ion will be discharged at the negative electrode?

• The ion of the most reactive element

• The ion of the least reactive element

• The ion with the highest charge

• The ion with the largest size

If copper ions and hydrogen ions are present, which will be discharged?

• Hydrogen ions

• Copper ions

• Neither copper nor hydrogen ions

• Both copper and hydrogen ions

What happens at the positive electrode if a halide is present?

• No discharge occurs

• The halide gets discharged

• The hydroxide gets discharged

• The metal ion gets discharged

What is formed at the negative electrode during the electrolysis of copper sulfate (CuSO4)?

• Sulfate ions

• Pure copper

• Oxygen gas

• Hydrogen gas

During the electrolysis of aqueous sodium chloride, what is discharged at the positive electrode?

• Hydroxide ions

• Chloride ions

• Sodium ions

• Hydrogen ions