Question

The enthalpy change involved in the oxidation of glucose is $-2880kJmo{l}^{-1}$ . Twenty five percent of this energy is available for muscular work. If 100 kJ of muscular work is needed to walk one kilometer, what is the maximum distance that a person will be able to walk after eating 120 g of glucose?

• A. 7.9 km
• B. 9.7 km
• C. 4.8 km
• D. 8.4 km

Answer 1

Answer: (C)

Total energy involved in the oxidation of glucose $=-2880$ $kJmo{l}^{-1}$ .
As twenty five percent of this energy is available for muscular work.
So energy available for muscular work $=\frac{2880\times 25}{100}=720$ $kJmo{l}^{-1}$
Energy available for muscular work from 120 g glucose $=\frac{720\times W_{glucose}}{molecularweight}=\frac{720\times 120}{180}=480kJ$
As 100 kJ energy is enough for = 1 km
so 480 kJ energy is enough for $=\frac{480\times 1}{100}=4.8km$