Hdzhthrsyjshf (1 Viewer)

[KoshX87]

Re: Your Inudstrial Chem answers

I think the weird part was trying to actually answer the last question properly. I think i provided enough info, but i couldn't manage to completely justify the statement. I talked about the Frasch and Contact processes, and so did a few other people, whereas a few friends stuck to just the contact process. What were the exact points we were meant to make, because in none of the textbooks I used wrote about environmental issues.
I kinda made them up, like SO3 being lost to the surroundings of the plant leading to acid rain (this is probably wrong) or how the fact that they make oleum prevents the H2SO4 gas from harming the environment by dissolving Iron and Calcium and also how, by making oleum first, less SO3 would get lost. It was such an annoying question in general, but hopefullya 5/6 or 7 if the markers actually approve of my nonsense

 

[KoshX87]

Re: Your Inudstrial Chem answers

Idk why but I just think it was important in showing why A was preferable over B and that the advantages of B (limestone) were not only limited to B (transport using train).

I could be wrong. I hope I am lol..

I strted by mentioning the adv and disadv of each plant, but went to show that A was better.

 

[ocatal]

Re: Your Inudstrial Chem answers

I think the weird part was trying to actually answer the last question properly. I think i provided enough info, but i couldn't manage to completely justify the statement. I talked about the Frasch and Contact processes, and so did a few other people, whereas a few friends stuck to just the contact process. What were the exact points we were meant to make, because in none of the textbooks I used wrote about environmental issues.
I kinda made them up, like SO3 being lost to the surroundings of the plant leading to acid rain (this is probably wrong) or how the fact that they make oleum prevents the H2SO4 gas from harming the environment by dissolving Iron and Calcium and also how, by making oleum first, less SO3 would get lost. It was such an annoying question in general, but hopefullya 5/6 or 7 if the markers actually approve of my nonsense

Said the same thing haha

 

[RealiseNothing]

Re: Your Inudstrial Chem answers

For 7 marker I wrote about only the contact process, some points I had:

1) In the conversion of S to SO2, to prevent a stable mist of acid forming, hot dry oxygen in excess must be used. This oxygen is dried by being bubbled through sulphuric acid. So to prevent this stable mist from impacting on the environment, we need to use some of our yield of sulphuric acid to dry the oxygen. Hence this is one compromise between yield and environmental impacts.

2) In the conversion of SO2 to SO3, we use relatively high temperatures and pressures. Too high of a temperature will cause thermal pollution though, and too high pressures can lead to explosions. So we sacrifice some yield of SO3 by lowering the temperature and pressure so that the environment is not impacted as badly. This is another compromise.

3) Now we could react SO3 with water to produce sulphuric acid. However this would be highly exothermic and produce a stable mist of acid. So instead we react the SO3 with sulphuric acid to produce oleum, which can then be react with water to produce the final sulphuric acid. We do this to avoid the thermal pollution of the highly exothermic reaction and to prevent the stable mist forming. In doing so, this decreases our final yield of sulphuric acid as some of it is reacted with the SO3. So this is yet another compromise.

 

[Infntie]

Re: Your Inudstrial Chem answers

Just clarifying 32a)
1. Describe soap's structure (apparently it could have been a detergent but highly doubt that) in terms of its non-polar alkyl tail and polar COO- head.
2. Non-polar alkyl chain 'pierces' the grease, interacting with it through dispersion forces while its polar head simultaneously interacts with water through hydrogen bonds. (debatable, I'm more for hydrogen bond that ion-dipole)
3. With agitation, grease molecule is lifted up from surface to form a micelle where the negative surfaces of it electrostatically repel other micelles, subsequently forming a stable emulsion that can be washed away, demonstrating how the grease can be removed.

 

[Infntie]

Re: Your Inudstrial Chem answers

RealiseNothing has some good points. Though including the Frasch process may improve the sophistication of your answer, going only into detail into the Contact process is fine too.
The main problem with the question was that the syllabus doesn't strictly teach how industries "compromise" between maximum yield and environmental impact but more towards yield and rate. Anyway, that just means we have freedom of expression - write whatever you think makes sense.
As for me, when I talked about Frasch process, I compared it to metal smelters (lol) in terms of how although the Frasch process may optimise yield of S(s) from which SO2(g) hence H2SO4(l) is formed, it has major environmental impacts (etc) and as a result, the industry had to compromise, using metal smelters instead which produce SO2(g) at a slower rate (this may not be true/bs) , directly sourcing the SO2(g) [ Zns + 3/2 O2 -> ZnO + SO2] which not only prevents the damage caused the Frasch process but eliminates the environmental damage (acid rain etc) that the released SO2(g) would have had (as it is a waste product).
Just my thoughts

 

[Menomaths]

Re: Your Inudstrial Chem answers

For 7 marker I wrote about only the contact process, some points I had:

1) In the conversion of S to SO2, to prevent a stable mist of acid forming, hot dry oxygen in excess must be used. This oxygen is dried by being bubbled through sulphuric acid. So to prevent this stable mist from impacting on the environment, we need to use some of our yield of sulphuric acid to dry the oxygen. Hence this is one compromise between yield and environmental impacts.

2) In the conversion of SO2 to SO3, we use relatively high temperatures and pressures. Too high of a temperature will cause thermal pollution though, and too high pressures can lead to explosions. So we sacrifice some yield of SO3 by lowering the temperature and pressure so that the environment is not impacted as badly. This is another compromise.

3) Now we could react SO3 with water to produce sulphuric acid. However this would be highly exothermic and produce a stable mist of acid. So instead we react the SO3 with sulphuric acid to produce oleum, which can then be react with water to produce the final sulphuric acid. We do this to avoid the thermal pollution of the highly exothermic reaction and to prevent the stable mist forming. In doing so, this decreases our final yield of sulphuric acid as some of it is reacted with the SO3. So this is yet another compromise.

I got all this minus the bolded iirc

 

[hamstar]

Re: Your Inudstrial Chem answers

32a)
Step 1: Soap added
Step 2: Soap forms bonds with grease/water
Step 3: Agitated and lifted off surce + washed away with water

Obviously analyzed that in more detail, so 3/3?

Does it have to be soap? Why not detergent???

That is why i put surfactant instead of soap/detergent. Will writing surfactant instead of soap/detergent be correct?
Because soap and detergent are different types of surfactants.

 

[Menomaths]

Re: Your Inudstrial Chem answers

Does it have to be soap? Why not detergent???

That is why i put surfactant instead of soap/detergent. Will writing surfactant instead of soap/detergent be correct?
Because soap and detergent are different types of surfactants.

That should be fine. I just hope they're not anal about me saying soap

 

[hamstar]

Re: Your Inudstrial Chem answers

In the end i put like a summary that:
A is closer to the ocean, so wastes can be easily disposed of.
It is closer to the town and the Na2CO3 market
And finally, I wrote that possibly there are other industries nearby (such as petroleum or natural gas and/or ammonia plants), because they'd also want to be near the city for their markets and hence the different industries could integrate.

You could have also included that site A is near a city/town which is already established. Therefore the solvay industry does not have to build a new residential area i.e. houses, transport systems, shops and schools for solway plant workers whereas at Site B, the solvay industry needs to develop a new residential area for workers.
You could have also mentioned that solid limestone is easier and economically cheap to transport than liquid brine. Hence site A is a suitable area.

 

[hamstar]

Re: Your Inudstrial Chem answers

That should be fine. I just hope they're not anal about me saying soap

Thanks man, this thread got me worried a bit. But i think they should not be that anal as heaps of students that do chemistry do not even know what the structure of a soap is. So i guess you should be fine.

 

[Plaguesbread]

Re: Your Inudstrial Chem answers

For the plant question,
Part a) I wrote the whole process because why teh fuck would i learn it and then NOT write them all? But I gave the overall one and I mentioned howit's a crucial material for the solvay process.

Part b) I mentioned that it's 100km (using the scale.. I mean they gave us a scale to use, why not use it?) away from a town, and would be hard for labor/transport. However, if positioned at A, there's rail tracks and can ship the Limestone easily.
It can also dispose of CaCl2 (coolant in water etc), ease of labor, ease of selling, actually is pretty damn close to getting reagets/materials from a large industry (ammonia for starting, although I did mention that it's recycled) and whatever else.
I mentioend some other things but sweg.

 

[superSAIyan2]

Re: Your Inudstrial Chem answers

for the soap question i wrote:

Step 1: The surfactant ion of the soap reorientates itself so that non-polar hydrocarbon tails can interact with non-polar grease molecules via dispersion forces.
Step2: Non-polar hydrocarbon tails penetrate the grease and form a micelle. The polar carboxylate head remains in the water and attracts water molecules via hydrogen bonds. This stabilises the micelle and allows it to be evenly dispersed in the water.
Step 3: Upon agitation the soap completely removes the grease from the material as a stable micelle, and due to repulsion between the negatively charged surface of the micelles they do not coalesce.

Is this correct?

 

[Menomaths]

Re: Your Inudstrial Chem answers

for the soap question i wrote:

Step 1: The surfactant ion of the soap reorientates itself so that non-polar hydrocarbon tails can interact with non-polar grease molecules via dispersion forces.
Step2: Non-polar hydrocarbon tails penetrate the grease and form a micelle. The polar carboxylate head remains in the water and attracts water molecules via hydrogen bonds. This stabilises the micelle and allows it to be evenly dispersed in the water.
Step 3: Upon agitation the soap completely removes the grease from the material as a stable micelle, and due to repulsion between the negatively charged surface of the micelles they do not coalesce.

Is this correct?

Pretty much what I wrote...So should be

 

[superSAIyan2]

Re: Your Inudstrial Chem answers

Pheww... thankss

 

[RealiseNothing]

Re: Your Inudstrial Chem answers

for the soap question i wrote:

Step 1: The surfactant ion of the soap reorientates itself so that non-polar hydrocarbon tails can interact with non-polar grease molecules via dispersion forces.
Step2: Non-polar hydrocarbon tails penetrate the grease and form a micelle. The polar carboxylate head remains in the water and attracts water molecules via hydrogen bonds. This stabilises the micelle and allows it to be evenly dispersed in the water.
Step 3: Upon agitation the soap completely removes the grease from the material as a stable micelle, and due to repulsion between the negatively charged surface of the micelles they do not coalesce.

Is this correct?

The only potential problem I can see is that the micelle forms AFTER the grease is removed from the surface.

 

[Jimmy2064]

Re: Your Inudstrial Chem answers

Yep I went A too, didn't even see the scale (oops). Doesn't matter though still mentioned all the points so should be good!

I guess neither did the girl in my class who's ranked 1st, went with B lol... then again I guess if you could argue it well enough you'd still get marks.

 

[Makematics]

Lol i never learnt soaps, lucky we only got a 3 marker