Electrochemistry Concepts for Grade 11

What is an electrochemical cell?

• A type of battery that cannot be recharged.

• A device that only stores electrical energy.

• An electrochemical cell is a device that converts chemical energy into electrical energy or vice versa.

• A machine that generates heat from chemical reactions.

Describe the function of the anode in an electrochemical cell.

• The anode is where reduction occurs and electrons are absorbed.

• The anode is the electrode where oxidation occurs and electrons are released.

• The anode is the electrode that generates heat during the reaction.

• The anode is responsible for the flow of ions in the electrolyte.

What is the role of the cathode in an electrochemical cell?

• The cathode is the site of reduction in an electrochemical cell.

• The cathode produces electrons in an electrochemical cell.

• The cathode is the site of oxidation in an electrochemical cell.

• The cathode is where the electrolyte is stored in an electrochemical cell.

Explain the difference between galvanic and electrolytic cells.

• Galvanic cells require electricity to operate; electrolytic cells generate electricity from reactions.

• Galvanic cells are used in batteries; electrolytic cells are used in light bulbs.

• Galvanic cells can only operate in acidic solutions; electrolytic cells can only operate in basic solutions.

• Galvanic cells generate electricity from spontaneous reactions; electrolytic cells require electricity to drive non-spontaneous reactions.

What is an electrolyte?

• An electrolyte is a substance that produces ions in solution and conducts electricity.

• A gas that forms bubbles in a solution

• A solid that does not conduct electricity

• A liquid that cannot dissolve in water

List two types of electrolytes and provide examples.

• Sodium Bicarbonate (NaHCO3)

• Calcium Carbonate (CaCO3)

• Potassium Hydroxide (KOH)

• 1. Strong Electrolyte: Sodium Chloride (NaCl), 2. Weak Electrolyte: Acetic Acid (CH3COOH)

How does temperature affect the conductivity of an electrolyte?

• Temperature has no effect on conductivity.

• Conductivity is only affected by concentration, not temperature.

• Higher temperatures decrease conductivity.

• Temperature increases the conductivity of an electrolyte.

What is the significance of the salt bridge in an electrochemical cell?

• It generates electricity by itself without any external circuit.

• It serves as a barrier to prevent any ion movement between half-cells.

• The salt bridge is significant because it maintains electrical neutrality and allows ion flow between half-cells in an electrochemical cell.

• The salt bridge is used to increase the temperature of the cell.

Define oxidation and reduction in the context of electrochemical reactions.

• Oxidation is the gain of protons; reduction is the loss of protons.

• Oxidation is the transfer of heat; reduction is the transfer of cold.

• Oxidation is the loss of mass; reduction is the gain of mass.

• Oxidation is the loss of electrons; reduction is the gain of electrons.

What is the Nernst equation used for?

• To calculate the mass of reactants in a reaction.

• To determine the temperature of a chemical reaction.

• To measure the concentration of a solution.

• The Nernst equation is used to calculate the cell potential of electrochemical cells under non-standard conditions.