Transcript Slide 1

The sun supplies energy at a rate of about 1.0
kilowatt per square meter of surface area (1 watt
= 1 J/s). The plants in a agricultural field produce
the equivalent of 20. kg of sucrose (C12H22O11)
per hour per hectare ( 1 ha = 10,000 m2).
Assuming that the sucrose is produced by5the
3.3 x 10 kJ
reaction:
1000 J
energy
4 J/s
J/s
9.29.2
x 10
12 CO2 + 11 H2O →
s
hr
C12H22O11 + 12O2
2
2
2
DH = 5640 kJ
m
m
10000m
0.92% efficient
Calculate the percentage of sunlight used to
produce the sucrose, that is determine the