The graph of volume of gas produced against time for a reaction produces a curve that becomes horizontal. What does the horizontal section of the graph indicate?

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Question

The graph of volume of gas produced against time for a reaction produces a curve that becomes horizontal. What does the horizontal section of the graph indicate?

Accepted Answer

One or more reactants have been completely used up — When the graph becomes horizontal (flat), no more gas is being produced, which means the reaction has stopped because one or more reactants have been completely consumed. At IGCSE, this reaction going to completion means a limiting reactant is used up. The reaction does not reverse under these conditions, the rate has actually fallen to zero not increased, and there is no requirement for temperature to drop to zero.

Answer

One or more reactants have been completely used up

Answer

The reaction has reached equilibrium and is reversing

Answer

The temperature of the reaction mixture has dropped to zero

Answer

The rate of reaction has increased to its maximum value

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