POSTLAB QUESTIONS

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1. For your reaction in this experiment, what is the half-life at 20.0 ¾C? (Show calculations.)

2. Use your first or second order graphs (ln of concentration or vs. time) you just prepared to determine the concentration of reactant remaining after 27 seconds at a temperature of 40.0 ¾C. First locate 27 seconds on the time axis and then follow it up to its intersection with the 40.0 ¾C line. Follow that horizontally to the y-axis and interpolate the value and then calculate the concentration in units of molarity.

3. Use the Arrhenius graph (ln k vs. 1T ) you just drew to determine the rate constant at 35.0 ¾C. First you will need to convert the temperature to Kelvin; next calculate the reciprocal of the Kelvin temperature; finally, locate reciprocal on the x-axis and then follow it up until it intersects with the line of the graph. Follow that to the y-axis and interpolate the value and calculate the rate constant.