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LOLyou actually calculated the MOLES OF H2 gas
i got confused by all the standard forms i kept my answers in fractions na
bus phir tu relax and wait for your A to come if the rest of your paper also went great 
DUDE aluminium does burn with light yellow flame to give rise to pale yellow aluminium chloride you are correct and you dont loose marks here ..... official revision guide for A levels says this
Hodder Education is the publisher .... David Bevan the author it is endorsed by CIE and it is the official guide for A and AS level
i cant upload pics but am sure you can get it from somewhere and see it for yourself but let me assure you that is the correct answer or just look it up on net
i am pretty sure you are mixing this up with Aluminium oxide which burns brightly with white flame and gives white powder
Aluminiums reaction with chlorine on other hand is vigorous giving pale yellow product
Hey can u do me a favour and confirm one more thing with ur sir. Ask him that for the part in which we had to give the effect of conditons on rate of formation of methanol i wrote for temp that. = The temperature provided is low and so the r.o.f will be less bcz average kinectic energy of molecules decrease and less effective collision occurs. The temp is considered low becz for normal commercial processes the temp used is around 750K and since rx is exo low temp is preferdBy the way guys, that Enthalpy Change was -129. I remembered the whole question, so I confirmed it with my Chem sir, and even with the textbook... I drew the Hess Cycle correctly according to the book, and then resolved the question, and still got -129 as the answer. My Sir confirmed it that the reaction was supposed to be exothermic... Al-Hamdulillah
plz man confirm this Yep, it should be. Many mistaked the enthalpy change of combustion for the enthalpy change of formation and the answer came positive.By the way guys, that Enthalpy Change was -129. I remembered the whole question, so I confirmed it with my Chem sir, and even with the textbook... I drew the Hess Cycle correctly according to the book, and then resolved the question, and still got -129 as the answer. My Sir confirmed it that the reaction was supposed to be exothermic... Al-Hamdulillah
Nope, the answer is:Hey can u do me a favour and confirm one more thing with ur sir. Ask him that for the part in which we had to give the effect of conditons on rate of formation of methanol i wrote for temp that. = The temperature provided is low and so the r.o.f will be less bcz average kinectic energy of molecules decrease and less effective collision occurs. The temp is considered low becz for normal commercial processes the temp used is around 750K and since rx is exo low temp is preferd
Because the previous question was the observation for the reaction. Do you think they will cut that mark too because my reaction was wrong? No, the marking scheme usually says 'allow ecf for wrong answer in the previous question' so you will gain marks if your answer is correct, even when it depends on the wrong answer you formerly calculated, or wrote, for that matter.My paper went good Alhamdulillah.
But I made some REALLY silly mistakes!.
Like, the reaction for Aluminium and Chlorine, in question 1,
I accidentally gave the reaction for Aluminium Oxide and Chlorine because I wasn't paying attention :S.. I know its so stupid!
The other answers before the question were alright, but this mistake was so stupid, do you think the examiner might get angry and deduct marks for the previous question as well ? Are the examiners allowed to do that ?
I made another silly mistake witht he reaction of Methanol and Oxygen. I gave Methanol as a gas! I was not paying attention at all.
I did not say anything about equilibrium. Mentioning the word equilibrium would have cost anyone the whole question itself. But i said that number of effective collisions would increase, and hence the rate of reaction, and probably the yield too, for that matter, but its not totally wrong as you indicate.
Man they specifically said that use the condition/something to answer. It wasn't the equilibrium one and what i meant was temp is directly propotional to R.O.F i just said low temp so less rate. I want u to confirm is that will he give me marks caz most people wrote the same but high temp. high R.O.F i wrote LOW tmep Low R.O.F sense is the same in both
I guess that's right.Man they specifically said that use the condition/something to answer. It wasn't the equilibrium one and what i meant was temp is directly propotional to R.O.F i just said low temp so less rate. I want u to confirm is that will he give me marks caz most people wrote the same but high temp. high R.O.F i wrote LOW tmep Low R.O.F sense is the same in both
Burning in chlorine
But sodium burns with white flame. In the field of science white is not regarded as a colorIt was burning in Chlorine. Its not confirmed that Sulfur burns in a blue flame in Chlorine, I'm 90% sure that Sulfur burns in a yellow flame in a chlorine atmosphere; producing a dark yellow liquid (S2Cl2).
Sodium was more correct, and safer.
I screwed up this question big time. I lost like at least 2 marks here just because of sheer stupidity, even though I knew the correct answers.
Bleh.
Anyways, the correct observations were; white sparks, white solid produced, or yellow color of gas disappears.
Then I turned Aluminum chloride's reaction with water as Basic. >_< I wrote it as Acidic (ph 3), then I crossed it and wrote pH8. >_< How idiotic of me.
Question 1: The table in which the reactions of chlorides with water were asked;- was it worth 3 marks or 6?
Question 2: When writing the pH of SiCl4's reaction with water, I wrote 3-4. In the Book it says 2. Will mine be accepted or not?
Question 3: What was the enthalpy change of formation of Methanol? I got -129 kJ mol-1.
Question 4: How do we know that, one of those organic compounds we were told to draw the structure of; that contained 2 Alcohol groups?
Question 5: What was the empirical formula they asked us to calculate? I got C6H8O7 or something...
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