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lol nice

You didn't have to convert anything to ammonia though. You just had to find the moles of ammonia and because there is only one nitrogen atom in a molecule of hydrogen then there will be the same number of moles of nitrogen present as ammonia.

You don't lose marks if you based a second part of a question on the first part. You'll lose marks in the first part but shouldn't in the second if your method is correct.

I hope not. I just said pressure on total system was reduced, shifting equilibrium to the right.

FML. Dammit i put it as well. Good thing its only one mark.

I think i can get 80+ if i havn't made too many silly errors, and 90+ might just be possible. I'm not sure really.

I don't think so. It means you have to find out how many moles of ethanol have been combusted using: 1367=mCAT/n you can find mCAT so you solve for the moles of ethanol and then multiply this value by 2 because if half the heat is lost then you need twice as much to give the same total...

I though endpoint was when the titration stopped and the colour change had already occured, not the point at which it occured. I'm known to be wrong so i'll take your word for it.

It's not wrong in the normal sense because cellulose is a natural resource and it can be used to industrially produce plastics similar to those made from polyethylene, but it depends upon how strict the marking criteria is for the question. I think if you used cellulose you will probably still...

petrol is a natural resource. As i said before, i think people were confusing natural and renewable.

Pressure wont change the total amount of each substance present but it will change how much of each substance is present per unit volume, or concentration for short.

No it was because phenolpthalein has a significant colour change of about 8-10 pH, which was in the range of both titration equivilence points

Its fertilisers im pretty sure.

You had to work backwards to find the moles of ammonia present and thus the moles of Nitrogen and use that to determine the mass of N and hence the %w/m. I think i got 1. 78% or something similar

Pressure does have a major effect on concentration where gases are concerned. If the pressure was increased, the concentration would increase sharply. It follows that if the pressure were to decrease, then concentration would decrease sharply. The reason the products increased is because of the...

I got 5 something for the K value

The way i did this question was to work out the moles of NaOH using n=CV. I then (and i think this is the part i did wrong) assumed that because citric acid is tripotic, then you would need three times as much NaOH to neutralise it. Using this assumption i worked out the moles of cirtric acid...

Lol i reckon. So was the question that asked for THE major use of sulfuric acid. I said fertilisers, but i was surprised by it. Normally it just asks for ONE major use.

It was: increase in temperature, as the system was endothermic, shifting equilibrium to the right Removal of CO, shifting equlibrium to the right Decrease in pressure on the system (they all decreased by the same amount, i thought), shifting the equilibrium to the right.

I think i got 5 something grams. I cant remember. Dammit if i did and everyone else got 3. My method was to find the heat of energy like the OP did, then used that to find the moles of ethanol used: 1367 (given) = 57.xxx/n solved for n and multiplied by 2 to account for half the heat lost...