Answer: water.
- A hydrogen peroxide
- B hydrogen gas
- C water
- D oxygen gas
Correct answer: C. water
Explanation: H<sub>2</sub> is oxidised and O<sub>2</sub> is reduced, and the two combine to give only water, making the cell pollution-free.
In a Daniell cell, electrons flow externally from the zinc anode (oxidation) through the voltmeter to the copper cathode (reduction), while the salt bridge completes the circuit.
Concept context
Explore the link between chemical reactions and electricity. Covers galvanic cells, electrolysis, standard electrode potentials, the Nernst equation, and real-world applications like batteries and corrosion.