3.3 Electrolysis

• What is electrolysis?

  Breaks down ionic compounds
• What happens at the anode during electrolysis?

  Negative ions are discharged
• What elements are formed at the cathode?

  Metals, Hydrogen
• The cathode is the positive electrode where cations are discharged.

  False
• The electrolyte is an ionic compound that conducts electricity
• What is the role of the anode in electrolysis?

  Discharges negative ions
• Why is reactivity important in electrolyte selection?

  Ensures oxidation and reduction
• Which common ionic compound is often used as an electrolyte?

  Sodium chloride
• The reactivity of ions in the electrolyte ensures oxidation and reduction occur during electrolysis.


  True
• Factors to consider when selecting electrode materials for electrolysis

  1️⃣ Reactivity

  2️⃣ Conductivity

  3️⃣ Availability and Cost
• Graphite is widely available and relatively inexpensive, making it a common choice for electrode material.

  True
• Anions lose electrons and undergo oxidation at the anode during electrolysis.

  True
• During electrolysis, cations move towards the cathode and anions towards the anode.


  True
• Match the electrolysis component with its function:

  Electrolyte ↔️ Conducts electricity, provides ions

  Cathode ↔️ Reduces cations at the negative electrode

  Anode ↔️ Oxidizes anions at the positive electrode
• More reactive ions in the electrolyte are preferred as they undergo reduction and oxidation
• The ideal electrolyte should have high conductivity, suitable reactivity of its ions, and be easily accessible and affordable.


  True
• The choice of electrode material depends on the specific electrolysis process and desired products.


  True
• Match the electrode with its charge transfer process and product:

  Cathode ↔️ Reduction, forms metals or hydrogen

  Anode ↔️ Oxidation, forms nonmetals or oxygen
• Unlike standard chemical equations, electrolysis equations explicitly show the movement of electrons
• During the electrolysis of molten CuCl₂, solid copper is formed at the cathode.


  True
• The cathode is the positive electrode in electrolysis.

  False
• Match the electrode with its polarity and ions discharged:

  Cathode ↔️ Negative, Cations

  Anode ↔️ Positive, Anions
• The ionic compound in an electrolysis setup that conducts electricity is called the electrolyte
• Which type of ion is discharged at the cathode?

  Cations
• The cathode is the negative electrode where cations are discharged.


  True
• Factors to consider when selecting an electrolyte for electrolysis

  1️⃣ Conductivity

  2️⃣ Reactivity

  3️⃣ Availability
• The ideal electrolyte for electrolysis should have high conductivity and suitable reactivity
• Conductivity is the ability of an electrolyte to conduct electricity.

  True
• Common compounds like sodium chloride or copper sulfate are ideal for electrolysis due to their availability
• Common compounds like sodium chloride or copper sulfate are ideal for electrolysis due to their availability
• The electrode material should be less reactive than the ions in the electrolyte to avoid unwanted reactions.


  True
• During electrolysis, cations move towards the cathode
• Electrolysis uses an electric current to break down ionic compounds into their constituent elements
• The three main components of an electrolysis setup are the electrolyte, the cathode, and the anode.

  True
• Factors to consider when choosing electrode materials

  1️⃣ Reactivity

  2️⃣ Conductivity

  3️⃣ Availability
• What is the reactivity of the electrode material relative to the ions in the electrolyte?

  Less reactive
• Which electrode do cations migrate towards during electrolysis?

  Cathode
• Steps for balancing electrolysis equations using the half-reaction method:

  1️⃣ Write the oxidation half-reaction at the anode

  2️⃣ Write the reduction half-reaction at the cathode

  3️⃣ Combine the balanced half-reactions
• What determines which ions are preferentially discharged during electrolysis?

  Reactivity series
• What is the role of electrolysis in producing hydrogen fuel?

  Splitting water