ALL CIE CHEMISTRY DOUBTS HERE !!

[narnia]

M/J 02, p1, ques.13,21,27....I hv the ans.,  but how??

[elemis]

M/J 02, p1, ques.13,21,27....I hv the ans.,  but how??

Question 13

Al2O3 is amphoteric and will react with the alkaline solution.

SO2 disolves in NaOH and is neutralised.

SiO2 reacts with NaOH to form Na2SiO3 and water.

By process of elimination MgO is the only possible answer.

Question 21

I'm not going to do this for you. Draw each and every possibility out on a sheet of paper and think of all possible placements of the Cl.

Question 27

Ethane is a gas so it is eliminated.

Potassium manganate(VII) would oxidise Ethanol to a carbonyl compound, so it is eliminated.

Ethanoic acid has a permanent dipole allowing for hydrogen bonding between H2O and its molecules. Hence, it mixes well with water. Thus, it is eliminated.

Ethyl Ethanoate is the answer as per process of elimination.

[narnia]

Excuse me please, the answer to question 13 is MgO &  not Al2O3.
for question 21,I got confused by the formula given, so asked.
But I really appreciate & thank you for your consideration. =)

[elemis]

Excuse me please, the answer to question 13 is MgO &  not Al2O3.
for question 21,I got confused by the formula given, so asked.
But I really appreciate & thank you for your consideration. =)

My bad, I misread the question. I though we were talking about dissolving in WATER. It seems we have to consider NaOH as the solvent.

[narnia]

My bad, I misread the question. I though we were talking about dissolving in WATER. It seems we have to consider NaOH as the solvent.

no problems.
how can ch3ch2ch2ch3 can result from mixing ethane n cl2  in uv light?? =/

also, when temp increases, the boltzman distrbtn curve move to d right or left?
bcz as far i know, it moves to right n bcums broader n shorter, but in oct04 p1 q12, the corect ans is b...where it movd to d left...im sorry i cant attach the ppr since im on from a mobile device.

[elemis]

no problems.
how can ch3ch2ch2ch3 can result from mixing ethane n cl2  in uv light?? =/

You know that in free radical substitution of ethane an ethyl radical is formed, correct ?

Thus, in a resulting a termination step :

CH₃CH₂^* + CH₃CH₂^* ---> CH₃CH₂CH₂CH₃
 

[narnia]

You know that in free radical substitution of ethane an ethyl radical is formed, correct ?

Thus, in a resulting a termination step :

CH₃CH₂^* + CH₃CH₂^* ---> CH₃CH₂CH₂CH₃
 

godamn i just overlooked tht part...
anyways, can u please  answer the second part in my pevious post as well if possible?

[HUSH1994]

MJ 2006 Paper 1 Q3 & 10 please
In question 10 i know that the Kp is the pressure of the products over the reactants,which is p(NO2)^2
                                                                                                                             ----------
                                                                                                                             p(N2O4)
so how do you get the partial pressures for each

[elemis]

MJ 2006 Paper 1 Q3 & 10 please
In question 10 i know that the Kp is the pressure of the products over the reactants,which is p(NO2)^2
                                                                                                                             ----------
                                                                                                                             p(N2O4)
so how do you get the partial pressures for each

Question 3

Nitrogen receives 3 electrons from Gallium to form an N^3- ion. Can you determine the answer by yourself now ?

Question 10

Lets say initially there were 2 moles of N2O4

50% of this dissociates, hence, 1 mole dissociates giving 2 moles of NO2 (use the molar ratio).

Partial pressure of molecule = no. of moles of molecule present at equilibrium/ TOTAL no. of moles at equilibrium

Can you do it now ?

[HUSH1994]

Thanks man i got it,sorry i meant Q2 not 3,3 is too easy

[HUSH1994]

MJ 2006 Paper 1 Q25 & 28 please

[elemis]

Thanks man i got it,sorry i meant Q2 not 3,3 is too easy

The isotopes of Cl are 35 and 37.

Hence, you can have :

(35-37)⁺

(37-37)⁺

(35-35)⁺

Thus, only three.

[elemis]

MJ 2006 Paper 1 Q25 & 28 please

Question 25

Conisder the fact that the C-F bond is harder to break than a C-Cl bond.

Now do it for yourself.

Question 28

Think about the reaction between 2,4-Dinitrophenylhydrazine and carbonyl compounds.

[HUSH1994]

Thanks man,i really appreciate your help +rep,and By the way are you doing any AS/A2 exams?

[elemis]

Thanks man,i really appreciate your help +rep,and By the way are you doing any AS/A2 exams?

Yeah, I'm answering May/June of this year.