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Question Chain Thread !!! (1 Viewer)

benji6667

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Bored and studying for your trials? Looking for some chemistry related fun? Look no futhur, its the question chain thread :D

Rules: The post above you will ask a question (may be a calculation, theory question etc). You answer the question then post a question underneath your response.... simple enough?? This will be epic win and the cure the stress :D

Ok ill get the ball rolling:

Write the equation for the fermentation of glucose
 

tommykins

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回复: Question Chain Thread !!!

C6H12O6 -> 2C2H5OH + 2CO2 with yeast obv.

Discuss evidence available that depicts an increase in sulfur dioxide concentration within the atmosphere.
 

gonutsmate

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What is the element universally connected to chemistry?
 

benji6667

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fine ill ask a normal question... none of this universal bs (although my guess is Carbon)

list the chronological order of scientists to proposed accepted theories on acids + their contribution to the understanding of acids
 

xiao1985

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So what if one gets the question wrong?
Haven't done any real chemistry for 4 years now... hope I can still remmeber:

Lavoisier, Arhhenius [sp], Davy, Bronsted-Lowry, Lewis

Q: How many isotopes could the element with formula C3H8O have, name them.
 

midifile

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xiao1985 said:
So what if one gets the question wrong?
Haven't done any real chemistry for 4 years now... hope I can still remmeber:

Lavoisier, Arhhenius [sp], Davy, Bronsted-Lowry, Lewis

Q: How many isotopes could the element with formula C3H8O have, name them.
a. thats not an element, and b. molecules cant have isotopes.

Is the question meant to say, how many isomers does the molecule with the formula C3H8O have?

If so, 2 - propan-1-ol and propan-2-ol

Oh and btw, Davy came before arhhenius

EDIT: Oops, I forgot to ask a new question... qu: Describe the method of the synthesis of a synthetic biopoloymer. Assess the potential of biololymers such as this one for polymers currently produced from petrochmicals.
 
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squeenie

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I'll do that!

All synthetic polymers are formed by the process of addition polymerisation. Double bonds in the monomers break open to join with other monomers to form a polymer. Examples of synthetic polymers include polyethylene and polystyrene.

I'm assuming that the question was referring to cellulose. Biopolymers such as cellulose have great potential as a partial/complete replacement for polymers made from petrochemicals. Biopolymers are made from renewable resources (such as plant material), and are biodegradable. However, biopolymers are still relatively expensive to produce, and there are still some problems associated with biopolymers. These problems include low resistance to water, and durabilty.

Right. I'm sure I've probably missed a few points and made a few typos. Oh well.

From the 2002 CSSA trial: Discuss the advantages and disadvantages of using models in chemistry. Use examples to illustrate your answer.
 

Undermyskin

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Hix.

I choose Polylactide!

Ok, lactic acid can be obtained from milk whey or fermentation process of sugar. The molecules are obligomerized then dimerized to form polylactide with a catalyst being stannous octoate catalyst. (that's basically it)

It has a high potentiality to be used widely as the crude-oil resource diminishes (tho only 3% is used in petrochemical but this alternative can save huge amount of money!). To catch up with the demands for a safe, versatile, biodegradable (environmentally friendly) and sustainable material, polylactide provides a somewhat neutral net CO2 although there are requirements for energy input during fermentation and polymerization processes that need petrol. Its physical properties are similer to those of polystyrene and can be modified to resembles polypropylene's or polyethene's. So it can replace these three popular polymers if not considering the costs!

Other petrol-based polymers contribute to environmental issues and shrinking oil resource. blah blah.

Why do you like to ask so long questions?

Q: What is a model? Assess its advantages and limitations.

Sorry, it's the first question that came up to my mind.

And, isn't it Arrhenius?

What the? I was typing it first!!!!!!!!!
 

midifile

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Okay. Im gonna answer both questions in one.

A model is a visual (or other) representation of something that cannot be seen in real life, due to being too small, too big, take to long to occur, or occur to quickly. Models can be used to represent these things so they can be seen and studied.

Advantages: Allows us to be able to study something that would normally be unable to study. Also, some models are working models, allowing use to see its function (ie Esterification and polymerisation can be modelled using molymods, and the bond breaking and reforming processes can be seen).

Disadvantages: Models often oversimply things and reduce a lot of the required detail of concepts. Models are usually not to scale (ie with molymods you can not see the relative size of particles).

Question: Evaluate the use of sodium hydroxide as a primary standard
 

twilight1412

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im pretty sure its because its anhydrous its crap
it absorbs water from the surrounding environment and it adds to the weight throwing off your calculations
if im right feel free to post another
if im wrong someone else answer it :p
 

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