If `150 kJ` of energy is needed for muscular work to walk a distance of one km, than how much of gulcose one has to consume to walk a distance of five km, provided only `30%` energy is available for muscular work.The enthalpy of combustion of glucose is `3000 kJ mol^(-1)`

Explanation

Energy consumed for walking a distance of 5 km = 150 `xx` 5 kJ = 750 kJ
1 mole of glucose, `C_(6)H_(12)O_(6)` (180 g) gives theoretically energy = 3000 kJ
Actual energy available `=(30)/(100) xx 3000` = 900 kJ
Thus, for 900 kJ of energy, glucose required = 180 g
`therefore` For 750 kJ of energy glucose required `= (180)/(900) xx 750` = 150 g