Industrial qs (1 Viewer)

[paper cup]

This question, Q28 of the 2002 paper.
One of the reactions used to form sulfuric acid is the reaction of oxygen with sulfur dioxide under equilibrium conditions to form sulfur trioxide. Pre reaction the concentration of SO2 was 0.06, conc of O2 was 0.05, after equilibrium was reached, the conc of SO3 was 0.04

Letting the conc of SO3 be x,

Using ICE we have
SO2 O2 SO3
I 0.06 0.05
C 0.04 0.03
E 0.06 - x = 0.02, 0.05 - 0.5x = 0.03, 0.04

The initial concentration of the SO3 should be 0 but the answers give it at 0.04. Typo? Why does the is there no difference between the equilibrium and intial concentrations of SO3? I know you don't need to know it to calculate K but I'd like to know why.

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OK so sulfuric acid is a strong acid, meaning that it ionises close to 100%. Buuttt, in one of the answers, 2002 paper Q 28 c i) The success one answers refer to it 'ionising strongly but incompletely' what does this mean.
How come sulfuric acid ionises incompletely?
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And is there any here with the pracs for industrial chem? I need help with saponification observations - we didn't do the prac. And the Solvay modelling one as well.

--> observations with saponification - what happens after the oil is added, after the container is shaken for one minute and the layers were allowed to settle; after being shaken for a further 5 minutes and the layers allowed to settle?

Thanks, and big e-mwah from cherry to anyone who answers

 

[mitochondria]

Yes, it must have been a typo I had a look at it...

As for c) i), well, the first ionisation pK_a is uber negative (sort of ) but the second ionisaiton pK_a is 1.99 That should give you an idea of why they say incomplete, otherwise come back and ask again.

And *scratch head* I didn't do the IC option so I can't help you with the prac, sorry

Good luck and study hard!

 

[paper cup]

Yes, it must have been a typo I had a look at it...

As for c) i), well, the first ionisation pK_a is uber negative (sort of ) but the second ionisaiton pK_a is 1.99 That should give you an idea of why they say incomplete, otherwise come back and ask again.

And *scratch head* I didn't do the IC option so I can't help you with the prac, sorry

Good luck and study hard!

I forgot about the whole diprotic thing altogether -____- thanks! know anyone who did do industrial chem?

 

[mitochondria]

Goodie =) So you get it.

And I don't think I know anyone who did industrial chem... I'll let you know if come across someone

 

[sikeveo]

I forgot about the whole diprotic thing altogether -____- thanks! know anyone who did do industrial chem?

Whole of SHS, JRAHS, SGS this year, and JRAHS last yr.

 

[paper cup]

Whole of SHS, JRAHS, SGS this year, and JRAHS last yr.

I meant someone who is on the board at the moment and can answer my question.
also NSGH last year.

 

[jetfan]

Well I did both pracs so here it is:
After the oil was initially added, you had two layers, the oil and the water, with the emulsifier mixed in, then after shaking for one minute, you still had two layers, possibly a third because some soapy froth may form, after 5 minutes, there is usually two layers, a soapy layer and a watery layer, depending on the concentrations you use, you may still have a oily layer, We noticed that the shaking prac produced a liquidy soap, and it didn't foam in bore(hard) water.

With the modelling of Solvay, we did the final heating step.

2NaHCO3 --> Na2CO3 + H2O + CO2

We put a small sample of the sodium hydrogen carbonate in a delivery tube, we heated it over a bunsen, we put the hose from the delivery tube into a beaker of limewater, voila it turns milky because of the CO2. We then used some cobalt chloride paper, to test for the presence of H2O moisture. It turned from blue to pink. And we then has our final product.

Sorry if I've misse anything, we seemed to skim over these pracs quickly.

Good Luck

 

[paper cup]

Well I did both pracs so here it is:
After the oil was initially added, you had two layers, the oil and the water, with the emulsifier mixed in, then after shaking for one minute, you still had two layers, possibly a third because some soapy froth may form, after 5 minutes, there is usually two layers, a soapy layer and a watery layer, depending on the concentrations you use, you may still have a oily layer, We noticed that the shaking prac produced a liquidy soap, and it didn't foam in bore(hard) water.

With the modelling of Solvay, we did the final heating step.

2NaHCO3 --> Na2CO3 + H2O + CO2

We put a small sample of the sodium hydrogen carbonate in a delivery tube, we heated it over a bunsen, we put the hose from the delivery tube into a beaker of limewater, voila it turns milky because of the CO2. We then used some cobalt chloride paper, to test for the presence of H2O moisture. It turned from blue to pink. And we then has our final product.

Sorry if I've misse anything, we seemed to skim over these pracs quickly.

Good Luck

thank you
god, the chem forums are so much nicer than the math ones. I remember being.