Please answer in full, showing work. I’m trying to understand the concepts behin
ID: 146032 • Letter: P
Question
Please answer in full, showing work. I’m trying to understand the concepts behind this and I’m very confused! Thanks :) lucose and fructose are simple sugars with the molecular formula C,H120%. Sucrose, or table sugar, is a complex sugar with molecular formula C12H20u that consists of a glucose unit covalently bound to a fructose unit (a water molecule is given off as a result of the reaction between glucose and fructose to form sucrose) 1) Calculate the energy released as heat when a tvpical table sugar cube of mass 1.5 g is burned in air. 2) To what height could you climb on the energy a table sugar cube provides assuming 25% of the energy is available for work? 3) The mass of a typical glucose tablet is 2.5 g Calculate the energy released as heat when a glucose tablet is burned in air. 4) To what height could you climb on the energy a cube provides assuming 25% of the energy is available for work?Explanation / Answer
1) The energy released during a combustion reaction is given by
Q= - nH
Where ,n is the number of moles of the reactants and H is the enthalpy change .
number of moles is given by - weight given / molecular weight.
ThereforeQ = -1.5/ 342 x (-5645 ) = +25kJ.
b) Now we are given that we are provided 25% of the total energy , that means the energy provided is -
25/100 x 25 = 6.15 kJ .
Energy required to climb a height h is given by
E=mgh . The mass of the person is not given , so let us consider that to be 65 kg .
Therefore h = E/mg = 6.25/ 65x9.8 = 9.7m .
c) Again , applying the same formula ,
Q=-nH
We get , Q = -2.5 /180 x (-2808kJ) = 39kJ .
d) 25%of the energy is
25/100 x 39 = 9.75kJ
Height to which a 65kg person can climb with that energy is given by
H= E/mg = 9.75x 1000/ 65x9.8 = 15m