To determine which equation for photosynthesis is balanced, we can analyze each option. The overall balanced equation for photosynthesis in terms of the number of each molecule is:
\[ 6 \text{CO}_2 + 6 \text{H}_2\text{O} \rightarrow \text{C}6\text{H}{12}\text{O}_6 + 6 \text{O}_2 \]
Now let's evaluate the provided options:
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10H2O + 5CO2 → C6H12O6 + 15O2
- Reactants: 10 H2O and 5 CO2
- Products: 1 C6H12O6 and 15 O2
- Total Oxygen: 10 (from H2O) + 10 (from CO2) = 20 O on reactants side, and 6 (from glucose) + 15 = 21 O on products side. Not balanced.
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12H2O + 3CO2 → C6H12O6 + O2
- Reactants: 12 H2O and 3 CO2
- Products: 1 C6H12O6 and 1 O2
- Total Oxygen: 12 (from H2O) + 6 (from CO2) = 18 O on reactants side, and 6 (from glucose) + 1 = 7 O on products side. Not balanced.
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H2O + CO2 → C6H12O6 + O2
- Reactants: 1 H2O and 1 CO2
- Products: 1 C6H12O6 and 1 O2
- Total Oxygen: 1 (from H2O) + 2 (from CO2) = 3 O on reactants side, and 6 (from glucose) + 1 = 7 O on products side. Not balanced.
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6H2O + 6CO2 → C6H12O6 + 6O2
- Reactants: 6 H2O and 6 CO2
- Products: 1 C6H12O6 and 6 O2
- Total Oxygen: 6 (from H2O) + 12 (from CO2) = 18 O on reactants side, and 6 (from glucose) + 6 = 12 O on products side. This one is balanced.
The correct answer is: 6H2O + 6CO2 → C6H12O6 + 6O2