Setting up electrolysis experiment...
Water Molecule
H₂O - Click on particles to see details
Hydrogen Gas (H₂)
Oxygen Gas (O₂)
H⁺ Ions → Cathode (right)
OH⁻ Ions → Anode (left)
Water Molecules (H₂O)
12V
Applied Voltage
0
H₂ Molecules
0
O₂ Molecules
1.0x
Reaction Rate
Electrolysis Process
Electrolysis is the decomposition of water (H₂O) into hydrogen (H₂) and oxygen (O₂) gases using electricity. This model shows how ions move in the solution and where gases are formed.
Ion Movement in Solution:
- H⁺ ions (positive): Move toward the cathode (negative electrode on the right) and gain electrons to form hydrogen gas.
- OH⁻ ions (negative): Move toward the anode (positive electrode on the left) and lose electrons to form oxygen gas and water.
- Electrons: Move only in the external circuit, from cathode (−) to anode (+).
2H₂O(l) → 2H₂(g) + O₂(g)
Redox Reactions:
Electrolysis involves two half-reactions: oxidation at the anode and reduction at the cathode.
Oxidation at Anode (Positive Electrode):
4OH⁻(aq) → O₂(g) + 2H₂O(l) + 4e⁻
Hydroxide ions lose electrons (oxidation) to form oxygen gas and water.
Reduction at Cathode (Negative Electrode):
4H⁺(aq) + 4e⁻ → 2H₂(g)
Hydrogen ions gain electrons (reduction) to form hydrogen gas.
Overall Reaction: Combining both half-reactions gives the net decomposition of water into hydrogen and oxygen gases.
Key Observations:
- Hydrogen gas volume is twice that of oxygen gas (2:1 ratio)
- Electrons flow externally from cathode to anode
- Ions move internally: H⁺ to cathode, OH⁻ to anode
- Adding electrolyte (dilute acid) increases conductivity