To determine which of the equations is balanced correctly, we need to check if the number of atoms of each element on the reactant side equals the number of atoms of the same element on the product side.
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C6H5 + O2 → 2CO2 + 3H2O
- Reactants: C: 6, H: 5, O: 2
- Products: C: 2 x 1 (from CO2) = 2, H: 3 x 2 (from H2O) = 6, O: 2 x 2 (from CO2) + 3 x 1 (from H2O) = 4 + 3 = 7 (Oxygen is out of balance)
- Not balanced.
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CS2 + 3CI2 → CCI4 + S2CI2
- Reactants: C: 1, S: 2, Cl: 6
- Products: C: 1, S: 2, Cl: 4 (from CCl4) + 2 (from S2Cl2) = 4 + 2 = 6
- Balanced.
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B2O3 + 2C → B4C + CO
- Reactants: B: 2, O: 3, C: 2
- Products: B: 4 (from B4C), O: 1 (from CO), C: 1 (from CO) + 4 (from B4C) = 5
- Not balanced.
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CI2 + NaI → 2NaCI + I2
- Reactants: Cl: 2, Na: 1, I: 1
- Products: Cl: 2 (from 2NaCl), Na: 2 (1 from each NaCl), I: 2 (from I2)
- Not balanced.
From the above analysis, only the second equation CS2 + 3CI2 → CCI4 + S2CI2 is balanced correctly.