Question

3. Ethyl alcohol is produced by the fermentation of glucose, CH 206 CH20,(5) 2C,H,OH(1) + 2C02(8) AH° = -69.1 kJ How many kilojoules of heat is released when 25.0 grams of ethyl alcohol, C,H,OH are produced? 4. Write a balanced chemical equation for the formation reaction of glucose, C6H1206

Answer 1

The given balanced equation is

C6H12O6 --> 2C2H5OH + 2CO2 .. dH= -69.1 KJ

when 1 mole glucose fermented 2 mole alcohol produced
with the liberation of 69.1 KJ energy

It is given mass of alcohol produced = 25 g
we know molar mass of C2H5OH = 2*12.01 g/mol + 6*1.01 g/mol + 1*16 g/mol
= 46.07 g/mol
SO moles of C2H5OH produced = mass of alcohol/molar mass
= 25 g/46.07 g/mol = 0.5427 mols
when 2 mole alcohol is produced
the liberation of energy = 69.1 KJ
therefore 0.5427 mols C2H5OH releases 69.1 KJ/2 *0.5427 energy

energy released = 18.75 KJ

{Its enthalpy change = -18.75 KJ}
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glucose is formed from CO2 and H2O ;the reaction given below
6 H2O(g) + 6 CO2(g)------> C6H12O6(s) + 6 O2(g)
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thank you hope it is helpful