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ALL CIE CHEMISTRY DOUBTS HERE !!

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Deadly_king:

--- Quote from: komailnaqvi on November 19, 2010, 04:19:48 am ---thanx man.
J05 Q2 plz
+rep

--- End quote ---

Anytime dude :)

Hmm.................you have been given an equation where 2 moles of Sodium azide forms 2 moles of sodium and 3 moles of nitrogen.

Divide everything by 2 so as to get the equation resulting from one mole of sodium azide. You'll get 1.5 moles of nitrogen and 1 moles of sodium.

But from second equation provided, you'll note that 10 moles of sodium form one mole of N2. So the one mole of sodium formed above will form only 0.1 mole of N2.

Total number of moles of nitrogen produced will be 1.5 + 0.1 = 1.6

Answer is B

komailnaqvi:
ohh Chicken! thanxx man!

$!$RatJumper$!$:

--- Quote from: Deadly_king on November 19, 2010, 04:12:26 am ---Nov 04 No 10

2H2O(g) <==> 2H2(g) + O2(g)

Initially there is only pressure of 1 atm due to steam.

                                  (H2O)                        (H2)                        (O2)
Initially                             1                              0                               0

At equilibrium                 1 - 2                          2                            

Since we have been told that 20% of the steam has been converted, this implies that there still remains 80% at equilibrium.

So 1 - 2 = (80/100) x 1 -----> = 0.1

So the total pressure at equilibrium will be [(1 - 2) + 2 + ] ----> Replace = 0.1 to get a total of 1.1 atm.

Now we can find each partial pressure at equilibrium by dividing by total pressure.

(H2O) = (1 - 2)/1.1 ----> 0.8/1.1
I'll let you find the other by yourself. ;)

Answer is D.

Jun 10 p11 No 40

Bromoethane has a lower boiling point(39oC) than the solution from which it is being made, so as it is formed, the heat supplied will cause it to evaporate and we'll be able to collect it using the apparatus shown.

Ethanal also has a lower boiling point(21oC) that the reactants producing it. So it can be successfully separated using the apparatus.

1, dibromoethane however has a much higher boiling points(132oC) than the other substances in the reacting mixture. Hence we'll not be getting it through this apparatus.

So answer is B.

Hope it helps :)

--- End quote ---

Excellent! :) Thank you very much! +rep

Deadly_king:
Anytime guys :)

Just ace the paper today ;D

Good luck to you all ;)

cs:
Good Luck to all of you.. Thanks for those who helped all my doubts. I am done with my papers already. Thanks Student Forums..

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