Humboldt State University ® Department of Chemistry

Richard A. Paselk

Chemistry 438 - Spring 2011

 Final Exam Study Guide

Supplement

1.     If the cycling provides heat to warm the insect, estimate the time required for a bee to raise its muscle temperature from 20.0 °C to 30.0 °C if the substrate cycling takes place at an average rate of 20.0 micromoles/min/g of muscle and all of the heat generated remains in the flight muscle.

(20.0 x 10-6 mol*min-1*g-1)*(30.0 x 103 J*mol-1)

= 0.600 J*min-1*g-1

(30.0 °C - 20.0°C)*(4.184 J*°C-1*g-1)

= 41.84 J*g-1

(41.84 J*3-1) / (0.600 J*min-1*g-1)

= 69.73 min

= 69.7 min

 

2.     Try a second, perhaps more realistic calculation, by assuming a cycling rate of 20 micromoles/min/g of muscle and an aerobic glycolytic rate of 16 micromoles/min/ g of tissue.

3.     Assumptions:

4.     Calculation

Energy from cycle + energy from glycolysis =

(20.0 x 10-6 mol*min-1*g-1)*(30.0 x 103 J*mol-1) + (16.0 x 10-6 mol*min-1*g-1)*(30 ATP)*(30.0 x 103 J*mol-1)

= 0.600 J*min-1*g-1 + 14.4 J*min-1*g-1

= 15.0 J*min-1*g-1

(30.0 °C - 20.0°C)*(4.184 J*°C-1*g-1)

= 41.84 J*mol-1

(41.84 J*mol-1) / (15.0 J*min-1*g-1)


Syllabus

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Schedule

Last modified 3 May 2011