Answer: Reaction A: pi + glucose ⇒ glucose-6-phosphate + H2O ΔG = 13.8 kJ/mol
Reaction B: pi + frutose-6-phosphate ⇒fructose-1,6-biphosphate + H2O ΔG = 16.3kJ/mol
Explanation: ΔG is the representation of the change in Gibbs Free Energy and relates enthalpy and entropy in a single value, which is:
ΔG = ΔH - TΔS
where:
ΔH is enthalpy
T is temperature
ΔS is entropy (measure of the )
It can also predict the direction of the reaction with the conditions of temperature and pressure being constant.
When the change is positive, the reaction is non-spontaneous, which means the reaction needs external energy to occur. If the change is negative, it is spontaneous, i.e., happens without external help.
Analyzing the reaction, we see that reaction A and B have a positive ΔG, while reaction C is negative, so the reaction that are unfavorable or nonspontaneous are <u>reactions A and B</u>.
Answer:
a) and d) are false.
Explanation:
a) The second law of thermodynamics states that t<u>he entropy of the universe increases in a spon
taneous process and remains unchanged in an equilibrium process.</u>
For a spontaneous process:
ΔSuniv = ΔSsys + ΔSsurr > 0
For a spontaneous process, the second law says that ΔSuniv must be greater than zero, but it does not place a restriction on either ΔSsys or ΔSsurr. Thus, it is possible for either ΔSsys or ΔSsurr to be negative, as long as the sum of these two quantities is greater than zero.
d) <u>A reaction that does occur under the given set of conditions is called a</u> spontaneous reaction. We observe spontaneous physical and chemical processes every day, including many of the following examples:
• A waterfall runs downhill, but never up, spontaneously.
• A lump of sugar spontaneously dissolves in a cup of coffee, but dissolved sugar does not spontaneously reappear in its original form.
• Heat flows from a hotter object to a colder one, but the reverse never happens spontaneously.
Answer/Explanation:
As bread is baked, the yeasts release carbon dioxide that causes the bread to rise. ... The yeast uses glycolysis and alcohol fermentation to break down sugars in the dough. The yeast releases alcohol and carbon dioxide as a waste product. The carbon dioxide gas causes the bread to rise.
