Please check out my answer for this Fermentation question? I don't know if i'm correc

[daominhhai129]

1.To make bread, flour, yeast and other ingredients are mixed into a dough. This is left to ferment in a warm place. After a while, the dough rises. It is then heated to five bread.
a. What are the two products of fermentation? (Alcohol and Carbon dioxide)
b.What cause the dough to rise?(Yeast)
c.The yeast ceases to act once the dough is heated. Why? (it is because at a particular temperature, the fermentation stops and the yeasts die)
d.Bread does not contain any alcohol. Suggest why not? (i don't know? Help me please.

[Sonic]

1.To make bread, flour, yeast and other ingredients are mixed into a dough. This is left to ferment in a warm place. After a while, the dough rises. It is then heated to five bread.
a. What are the two products of fermentation? (Alcohol and Carbon dioxide)

Almost correct, you should put Ethanol instead of Alcohol. In chemistry alcohol refers to a molecule of the type R-OH of which ethanol is one.

b.What cause the dough to rise?(Yeast)

It depends what the question is asking. The CO2 formed from the yeast causes it to rise but I would say CO2.

c.The yeast ceases to act once the dough is heated. Why? (it is because at a particular temperature, the fermentation stops and the yeasts die)

The enzymes denature so no further reaction proceeds.

d.Bread does not contain any alcohol. Suggest why not? (i don't know? Help me please.

Compare the boiling point of ethanol to that of the oven :p

[daominhhai129]

almost correct, you should put ethanol instead of alcohol. In chemistry alcohol refers to a molecule of the type r-oh of which ethanol is one.



It depends what the question is asking. The co2 formed from the yeast causes it to rise but i would say co2.



The enzymes denature so no further reaction proceeds.



Compare the boiling point of ethanol to that of the oven :p

thank you so much...ya now i can understand...BUT HOLD ON, the last one, i don't know what you mean : "Compare the boiling point of ethanol to that of the oven"..sorry i'm very suck...

[daominhhai129]

Please check out my answers.
3.In some agricultural countries, ethanol is used as a fuel for motor vehicles. Either pure ethanol or an ethanol-petrol mixture is used.
a)Name a raw material used for manufacturing the ethanol(Petroleum gas-CH4 or sugarcane C6H12O6) -->> i think this one is wrong cause raw materials must not be processed)
b. How is pure ethanol separated from the mixture( Using fractional distillation based on the difference on boiling point of Alcohol and mixture)
c.Give the main advantage of ethanol as a fuel compared with petrol(As petrol extracted from petroleum is not sufficient to supply for the whole world, ethanol obtained from Fermentation or reaction between Petroleum gas and steam in Catalyst are ways to produce fuel for vehicles)
d. Write the equation for the complete combustion of ethanol in air (Ethanol + Oxygen -> Carbon dioxide and water)
...I'M DOING MY EXERCISE TO PREPARE FOR THE FINAL COMING EXAM, AND I LOST MY ANSWER SHEET SO..PLEASE HELP ME..THANK U SO MUCH...

[Russ]

thank you so much...ya now i can understand...BUT HOLD ON, the last one, i don't know what you mean : "Compare the boiling point of ethanol to that of the oven"..sorry i'm very suck...

Compare the boiling point of ethanol (78 C) to the temperature of an oven used to bake bread (varies but at least 150+ C)
What does that tell you?


d. Write the equation for the complete combustion of ethanol in air (Ethanol + Oxygen -> Carbon dioxide and water)


When writing equations, always write in terms of elements

CH3CH2OH + 3O2 ---> 2CO2 + 3H2O

[daominhhai129]

Thank you thank you..ya..i'm so grateful to you...do you ...have email or anything that i can contact you easier.....?

[Sonic]

It's easier to make a thread :]

I imagine Russ checks this every day, I know I do. Also Russ is in Australia so is probably in bed now

[Russ]

New threads are a more effective way of getting help. Thanks sonic!