Methanol can be produced by the following reaction: CO(g) + 2 H2(g) → CH3OH(g)

Question

with the rate of reaction = (Δ[CH₃OH]) ÷ (Δt). If the rate of the reaction is written using the concentration of hydrogen the rate of the reaction = ___.

A) -1/2* (Δ[H₂]/Δt)

B) +2* (Δ[H₂]/Δt)

C) + (Δ[H₂]/Δt)

D) - (Δ[H₂]/Δt)

Answer 1

rate of reaction = ∆[CH₃OH]/∆t = -1/2∆[H₂]/∆t = -∆[CO]/∆t

Answer A

Answer 2

The reaction stoichiometry governs the relationship of the rates as well as the mole relations between the participants in a reaction. It works even better if you assign all reactants negative stoichiometric coefficients: then you account for reactants having negative rates and products having positive rates.

r_H2 ( 1 mole Methanol / -2 moles of H₂) = r_Methanol

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