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ALEKS Chemistry Answers: Balance Br₂ + I₂ → IBr₃

Atom conservation gives the smallest whole-number coefficient ratio 3:1:2, so the balanced equation is 3Br₂(l) + I₂(s) → 2IBr₃(g).

Question

Balance the chemical equation below using the smallest possible whole-number stoichiometric coefficients.$$\mathrm{Br_2(l)+I_2(s)\longrightarrow IBr_3(g)}$$

Answer

The balanced equation is

3Br2(l)+I2(s)⟶2IBr3(g).\boxed{3\mathrm{Br_2(l)}+\mathrm{I_2(s)}\longrightarrow2\mathrm{IBr_3(g)}}.

Derive the coefficients

Let the coefficients of mathrmBr2mathrm{Br_2}, mathrmI2mathrm{I_2}, and mathrmIBr3mathrm{IBr_3} be aa, bb, and cc.

  • Bromine balance: 2a=3c2a=3c
  • Iodine balance: 2b=c2b=c

Because cc must be even, start with the smallest possible value, c=2c=2. Then b=1b=1 and a=3a=3.

Check the atom counts

ElementReactantsProducts
Br3×2=63\times2=62×3=62\times3=6
I1×2=21\times2=22×1=22\times1=2

The coefficient set (3,1,2)(3,1,2) has no common factor greater than 1, so it is already the smallest whole-number ratio.

Evidence boundary

This answer balances only the formulas and physical-state labels in the ALEKS manual's locked example. It establishes atom conservation and the smallest whole-number coefficient ratio, but it does not establish reaction feasibility, mechanism, equilibrium, or yield.

Sources

These references support the concepts and methods used in the explanation above.

ALEKS Chemistry Answers: Balance Br₂ + I₂ → IBr₃ | Verla