Can anyone help me with any of the following?

Question

1. Structurally, how are biological fuel (sugar) and ‘exhausted’ wastes (CO¬2, H2O) different?

2. Where is the biological ‘energy’ in a molecule of sugar?

3. Glucose is broken down in order to synthesize ATP. Where is the ‘energy’ in glucose? Hint: Glucose is broken down by combining with oxygen to create CO2 and H2O. Hint: Natural gas is methane, CH4. Glucose, water, and carbon dioxide. How do they differ structurally?

4. Ethanol burns. CO2 and H2O do not. What does this tell you about the energy extraction efficiencies of fermentation vs. oxidative phosphorylation?

Answer 1

1. Overall, biological fuels have less stable bonds than the 'exhausted' wastes. If less stable bonds are broken to make more stable ones, energy is released.

For example, sugar has a lot of C-C bonds, C-O bonds and C-H bonds. It only takes between 340 kJ/mol and 420 kJ/mol to break each one of these bonds. That is much less than the 805 kJ/mol released when you form a C=O bond (like in CO2), or less than the 464 kJ/mol that is released when you form an O-H bond (like in H2O).

2. and 3. (They are similar questions.) The energy is released when the bonds of the products (CO2 and H2O) are formed.
When a chemical reaction happens, it takes energy to break bonds, but then energy is released when the new bonds are formed.
It doesn't take too much energy to break sugar's bonds but a lot is released when it makes the bonds in CO2 and H2O.

4. The fact that ethanol burns, but that CO2 and H2O do not, tells you that ethanol has more chemical energy that can be released. This tells you that fermentation extracts energy less efficiently than oxidative phosphorylation.
We can deduce this because fermentation does not extract the energy that it would have gotten by turning ethanol into CO2 and H2O.

Answer 2

Structurally, ATP consists of the adenine nucleotide (ribose sugar, adenine base, and phosphate group, PO4-2) plus two other phosphate groups.

Fermenting glucose into Ethanol produces CO2:

C6H12O6 → 2 CH3CH2OH + 2 CO2

Buring Ethanol produces CO2:

C2H6O + 3 O2 → 2 CO2 + 3 H2O

Corn ethanol increases CO2. However, cellulosic ethanol burns 85% cleaner thatn corn ethanol and results in zero net carbon gain.

Answer 3

dont trip if you copy this down and get 0 / 10 on your hw.
CO2 is flat O=C=O, H2O is shaped like a triangle. Sugar is shaped like a boat.
2. sugar is broken down into ATP wich is your energy.. it comes from carbon
3. you should image-google these structures
4. it tells me i need to freshen up on biochem.

Answer 4

OK! You have definatley lost me.......... Sorry didn't bother reading point 2 onwards - way too technical for liitle ol me