Below is an energy profile of an exothermic reaction.

At the end of the experiment…

On plotting the appropriate form of your experimental values you will be expected to obtain the gradient and the y-intercept of a “line of best fit” using the method of least squares (section 4 of the “Estimation of Errors” in the beginning of your manual). Which of the following is the least squares formula given in your manual for the gradient, m?

In this experiment you are required to experimentally confirm the relationship: ln (1/t) =  constant - E_a / RT .

You will achieve this by determining the time taken, t, for a reaction to proceed to a certain extent at four different temperatures. Choose the plot that you would expect to yield a straight line.

In this experiment we perform reactions at four different temperatures and then plot ln(t) versus 1/T.

If we obtain a straight line from this plot which of these statements is most correct...

In this experiment you are required to experimentally confirm the Arrhenius relationship:

     ln (k) =  constant - E_a / RT .

OR equivalently, ln (1/t) =  constant - E_a / RT .

If this plot was obtained, what would be the value of the activation energy, E_a ?

Using an appropriate number of significant figures is extremely important in this experiment as round-off error can have a major effect on the results. Only the final value should be rounded off to the appropriate number of significant figures.

If you perform a reaction at 0.0 ^oC, what temperature should you therefore use in your Arrhenius law calculations?

The reaction S + 2 R → products has the rate law, rate = k [S][R]³

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The Arrhenius equation is an equation that shows the dependence of the rate constant, k, on activation energy, E_a, and temperature in Kelvin, T. Which one or more of the following form of the Arrhenius equation are valid?

Below is an energy profile of an exothermic reaction.