Question 1: Explain how a chemical cell in a battery converts chemical energy into electrical energy.

Answer: A chemical cell converts chemical energy stored in reactants into electrical energy through redox reactions occurring at the electrodes, producing a flow of electrons in an external circuit.

Question 1: Define an electrochemical cell.

Answer: An electrochemical cell is a device that uses redox reactions to generate electrical energy.

Question 2: Identify the function of the electrolyte in a battery.

Answer: The electrolyte allows ions to move between the electrodes, completing the circuit and enabling redox reactions.

Question 3: Describe the role of the electrodes in a typical chemical cell.

Answer: Electrodes serve as sites for oxidation and reduction reactions; the anode is where oxidation occurs and the cathode is where reduction occurs.

Question 1: Calculate the total voltage produced by a series connection of three cells, each producing 1.5 V.

Answer: 4.5 V

Question 2: A battery has a capacity of 2000 milliampere-hours (mAh). How much charge is stored in Coulombs? (Use 1 Ah = 3600 Coulombs)

Answer: 7200 Coulombs

Question 1: Describe a simple experiment to test the effect of different metals on the voltage produced in a cell.

Answer: Set up cells using different metal electrodes (e.g., copper, zinc, iron) with an electrolyte solution. Measure and record the voltage for each configuration using a voltmeter. Compare the voltages to determine which metal produces the highest potential difference.

Question 2: List three safety precautions to consider when handling batteries during practical experiments.

Answer: Avoid short circuits by not connecting the terminals directly; wear protective gloves and eye protection; handle batteries carefully to prevent leaks or ruptures.

Question 1: A series of experiments shows that a zinc-carbon battery produces a voltage of 1.5 V, while a lithium-ion battery produces 3.7 V under similar conditions. Explain why the lithium-ion battery provides a higher voltage.

Answer: Lithium-ion batteries have a higher electrochemical potential difference due to the more reactive nature of lithium and its ability to undergo redox reactions more readily than zinc, resulting in higher voltage output.

Question 1: Describe how rechargeable batteries are used in electric vehicles and the benefits they offer over traditional petrol engines.

Answer: Rechargeable batteries in electric vehicles store electrical energy that can be recharged multiple times, reducing reliance on fossil fuels. They produce zero emissions during operation, are quieter, and have lower running costs compared to petrol engines. Their use promotes sustainability and reduces air pollution.