Thursday, March 28, 2024
11:28 PM (GMT +5)

Go Back   CSS Forums > CSS Past Papers > CSS Papers (1971-2017) > CSS 2012 Papers

Reply Share Thread: Submit Thread to Facebook Facebook     Submit Thread to Twitter Twitter     Submit Thread to Google+ Google+    
 
LinkBack Thread Tools Search this Thread
  #1  
Old Sunday, March 04, 2012
Chintoo2010's Avatar
Senior Member
 
Join Date: Dec 2009
Location: Earth
Posts: 301
Thanks: 94
Thanked 270 Times in 131 Posts
Chintoo2010 will become famous soon enough
Arrow Chemistry papers 2012

Chemistry Paper I

Q No.2.
(i) Glucose is formed according to the following reaction, absorbing 2840 kJ of heat. How much energy will be given out by combustion of 1.08 of glucose? (4)
6CO2(g)+ 6H2O(l)C6H12O6(s) + 6O2 (g)
(ii) State and explain the relationship of ionization energy of an atom with its reactivity.
(iii) Explain: Why dipole movement of BF3 is Zero?
(iv) Why dipole movement of NH3is greater than that of NF3?
(v) Why does SO2 have dipole movement while CO2 does not?

Q No.3.
(i) Differentiate between a gangue and slag. Give an example of a metallurgical step where slag, flux, and gangue are involved simultaneously.
(ii) Describe the different industrial process for preventing the metals from corrosion.
(iii) Draw diagram extraction of aluminum from soil.
(iv) Name the flux used in the extraction of Iron.

Q No.4.
(i) Given the reaction: XeF4(g) + F(g)XeF6(g) (04) Predict the change in hybridization and consequent, final shape of the molecule followed in the above reaction.
(ii) Valence shell electron pair repulsion theory can be used to predict the shapes of molecules. Using this theory explain the shapes acquired by BF3 and CH4.
(iii) Explain why HOH bond angle in H2O is slightly less than the tetrahedral angle 109.5?

Q No.5.
(i) A galvanic cell consists of metallic Zn place immersed in 0.1 M Zn (NO3)2 solution and metallic plate of lead in 0.02 M Pb (NO3)2 solution. Given EoZn2 + Zn = -0.76 V, EoPB2 + Pb = -0.13 V Write the half cell reaction.
(ii) Write the overall reaction of the cell.
(iii) Calculate the e.m.f. of the cell.
(iv) Explain the Nernst heat theorem.
(v) Define enthalpy of formation.

Q No.6. Write one reaction each for the preparation of the following, Also write one use of each product.
(i) Bleaching Power
(ii) Caustic Soda
(iii) Quick Lime
(iv) Ammonia
(v) How is caustic soda manufactured by using Nelson's cell?
(vi) What is an ideal solution?

Q No.7.
(i) What do you understand by entropy? In what way the total entropy change is related to spontaneity of a system and to a system in equilibrium.
(ii) Entropy change from liquid water to steam at 373 K is 109J mol−1 K-1. What the enthalpy change for the transition of liquid water to steam at 373 K?
(iii) Define Gibbs free energy function. Explain its significance.
(iv) Explain following:
(a) Ion selective electrode
(b) Quantum yield
(c) Fuel Cell
(d) Langmuir isotherm

Q No.8.
(i) Why is chlorination not the most desirable method of disinfecting polluted water?
(ii) What are anthropogenic pollutants? Give two examples each of primary and secondary pollutants.
(iii) What are the effects of detergents on fresh water bodies?
(iv) Calculate the pH of 0.001 M HCl solution.
(v) How Global Warming is caused? List and explain four consequences of green house effect.
Reply With Quote
The Following 4 Users Say Thank You to Chintoo2010 For This Useful Post:
Ali Mallah (Monday, March 05, 2012), momina kanwal (Thursday, August 30, 2012), Naqash Fatima (Monday, March 05, 2012), Zinnia (Monday, March 05, 2012)
  #2  
Old Sunday, March 04, 2012
Chintoo2010's Avatar
Senior Member
 
Join Date: Dec 2009
Location: Earth
Posts: 301
Thanks: 94
Thanked 270 Times in 131 Posts
Chintoo2010 will become famous soon enough
Default

Q No.2.
a. What is the difference between Valence Bond Theory and Molecular Orbital Theory? (8)
b. Draw the Molecular orbital Diagram of CO molecule showing sigma, pi bonding, non-bonding and anti bonding molecular orbital. (8)
c. Discuss the difference between the Hybridization of SO2 and SO3. (4)

Q No.3.
a. Discuss the rate law of SN1 mechanism. (6)
b. What is the importance of half life in the determination of order of reaction? (6)
c. What is the pseudo first order reaction? What is its importance? (8)

Q. No. 4
a. Describe the difference between physical adsorption and chemiadsorplion. (8)
b. The data of Langmuir for the adsorption of Nitrogen and mica at 90 K given

....... ............. P (atm) ....... ........... ..2.8 ..... 3.4 .....4.0 .....4.9 ....6.0 .....7.3 ......9.4 .....12.8..... 17.9..... 23.5
------------------------------------------------------------------------------------------------------------------
Amt adsorbed cumm at 20K & 760MM ... 12.3 ... 13.4 ... 15.1 ...17.9 ...19.0 ...21.6 ....23.9 .....25.5 .....28.2..... 30.8

Estimate the surface area of the mica sample in the Langnuir experiment? (8)
c. Define Homogeneous catalyst & Heterogeneous catalyst. (4)

Q. No. 5
a. Discuss stereo isomerism in compounds having 2 similar asymmetric carbon atoms. (6)
b. Draw Fischer projection formulae of the following compounds. (8)
i) R & S 2 - Bromopentane
ii) R & S 3 - chloro-1-pentane.
iii) R & S 3-chloro-3-methylocatne
iv) R & S 2-pentanol
c. What do you understand by the terms Z & E isomers? Illustrate your answer with example. (6)

Q. No. 6
a. Discuss the structure of Grignard Reagent. (4)
b. How these compounds can be prepared by Grignard Reagent? (12)
i) Ethane
ii) Acetic Acid
iii) 2-Butanol
c. What is the diazotization reaction? (4)

Q. No. 7
How would you prepare the following compounds from Benzene? Name each reaction as well. (20)
i) Acetophenone
ii) Bromobenzene
iii) Maleic anhydride
iv) Toluene
v) Benzaldehyde

Q. No. 8
a. Write main steps in the formation of following polymers: (3+3)
i) Nylon 6,6 and polyester by condensation polymerization
ii) Polyethlene by Free Radical polymerization
b. Differentiate between oil, fat & wax with examples. (9)
c. What are alkaloids? (5)
Reply With Quote
The Following 2 Users Say Thank You to Chintoo2010 For This Useful Post:
momina kanwal (Thursday, August 30, 2012), Wali Ahad (Monday, March 05, 2012)
  #3  
Old Tuesday, March 06, 2012
Ali Mallah's Avatar
Senior Member
Qualifier: Awarded to those Members who cleared css written examination - Issue reason: CE 2012- Roll No 1988Medal of Appreciation: Awarded to appreciate member's contribution on forum. (Academic and professional achievements do not make you eligible for this medal) - Issue reason: PMS / PCS Award: Serving PMS / PCS (BS 17) officers are eligible only. - Issue reason: SPSC CCE 2013 - Merit 49 (ETO) BPS-17
 
Join Date: Feb 2012
Location: Hyderabad
Posts: 1,195
Thanks: 495
Thanked 1,546 Times in 864 Posts
Ali Mallah is a splendid one to beholdAli Mallah is a splendid one to beholdAli Mallah is a splendid one to beholdAli Mallah is a splendid one to beholdAli Mallah is a splendid one to beholdAli Mallah is a splendid one to behold
Default

Well chemistry paper is going to be complicated every year. Q.Paper is set in such a way so that student could not attempt all section i.e a,b,c,d,e of the single Question. This is not an encouraging trend specially for the science subjects. 3 MCQs and 2,3 Questions were repeated unexpectedly from 2011's paper.
Reply With Quote
  #4  
Old Wednesday, March 07, 2012
mfrehman1's Avatar
Member
 
Join Date: Nov 2011
Location: Lahore Cantt, Lahore
Posts: 58
Thanks: 3
Thanked 18 Times in 15 Posts
mfrehman1 is on a distinguished road
Default

I think paper is that difficult that I expected .... As I have studied chemistry upto Intermediate level.... Due to deep interest in chemistry now I am opting for chemistry for 2013...
__________________
mujhe chorh de mere haal par tera kia bhrosa aye humsfar
teri mukhtasar si nawazishein mera dard aur barha na dein.
Reply With Quote
  #5  
Old Thursday, March 08, 2012
Ali Mallah's Avatar
Senior Member
Qualifier: Awarded to those Members who cleared css written examination - Issue reason: CE 2012- Roll No 1988Medal of Appreciation: Awarded to appreciate member's contribution on forum. (Academic and professional achievements do not make you eligible for this medal) - Issue reason: PMS / PCS Award: Serving PMS / PCS (BS 17) officers are eligible only. - Issue reason: SPSC CCE 2013 - Merit 49 (ETO) BPS-17
 
Join Date: Feb 2012
Location: Hyderabad
Posts: 1,195
Thanks: 495
Thanked 1,546 Times in 864 Posts
Ali Mallah is a splendid one to beholdAli Mallah is a splendid one to beholdAli Mallah is a splendid one to beholdAli Mallah is a splendid one to beholdAli Mallah is a splendid one to beholdAli Mallah is a splendid one to behold
Default

Quote:
Originally Posted by mfrehman1 View Post
I think paper is that difficult that I expected .... As I have studied chemistry upto Intermediate level.... Due to deep interest in chemistry now I am opting for chemistry for 2013...
I'll suggest you not to opt chemistry, its really time taking and day by day its level is being raised. Paper is unexpected and above all paper II is lethal. I m doing Ph.D in chemistry but I could,t solve the whole paper this year.
Reply With Quote
  #6  
Old Thursday, March 08, 2012
mfrehman1's Avatar
Member
 
Join Date: Nov 2011
Location: Lahore Cantt, Lahore
Posts: 58
Thanks: 3
Thanked 18 Times in 15 Posts
mfrehman1 is on a distinguished road
Default

Quote:
Originally Posted by alimallah View Post
I'll suggest you not to opt chemistry, its really time taking and day by day its level is being raised. Paper is unexpected and above all paper II is lethal. I m doing Ph.D in chemistry but I could,t solve the whole paper this year.
In the above given paper what your were not able to solve ? Plz explain ..... I think all question are easily attempt able .... I will give chemistry 4 months ..... Insha allah
__________________
mujhe chorh de mere haal par tera kia bhrosa aye humsfar
teri mukhtasar si nawazishein mera dard aur barha na dein.
Reply With Quote
  #7  
Old Thursday, March 08, 2012
sumyra's Avatar
40th CTP (OMG)
CSP Medal: Awarded to those Members of the forum who are serving CSP Officers - Issue reason: CE 2011 - Merit 174
 
Join Date: Sep 2010
Location: punjab
Posts: 124
Thanks: 118
Thanked 139 Times in 60 Posts
sumyra will become famous soon enoughsumyra will become famous soon enough
Default

this is easy paper as compared to the previous year's..i didnt appeared this year but last year chemistry paper 1 was so much difficult..
__________________
“The greatest barrier to success is the fear of failure.”
Reply With Quote
  #8  
Old Friday, March 09, 2012
Ali Mallah's Avatar
Senior Member
Qualifier: Awarded to those Members who cleared css written examination - Issue reason: CE 2012- Roll No 1988Medal of Appreciation: Awarded to appreciate member's contribution on forum. (Academic and professional achievements do not make you eligible for this medal) - Issue reason: PMS / PCS Award: Serving PMS / PCS (BS 17) officers are eligible only. - Issue reason: SPSC CCE 2013 - Merit 49 (ETO) BPS-17
 
Join Date: Feb 2012
Location: Hyderabad
Posts: 1,195
Thanks: 495
Thanked 1,546 Times in 864 Posts
Ali Mallah is a splendid one to beholdAli Mallah is a splendid one to beholdAli Mallah is a splendid one to beholdAli Mallah is a splendid one to beholdAli Mallah is a splendid one to beholdAli Mallah is a splendid one to behold
Default

Quote:
Originally Posted by mfrehman1 View Post
In the above given paper what your were not able to solve ? Plz explain ..... I think all question are easily attempt able .... I will give chemistry 4 months ..... Insha allah
Well its easy to say from out the arena. Well if u feel then you can go ahead, it was only suggestion.

Quote:
Originally Posted by sumyra View Post
this is easy paper as compared to the previous year's..i didnt appeared this year but last year chemistry paper 1 was so much difficult..
Off course it was difficult as paper was not according to the trend of previous papers. Well I managed to take 116 in those papers. What was ur score in chemistry last year?
Reply With Quote
  #9  
Old Friday, March 09, 2012
Chintoo2010's Avatar
Senior Member
 
Join Date: Dec 2009
Location: Earth
Posts: 301
Thanks: 94
Thanked 270 Times in 131 Posts
Chintoo2010 will become famous soon enough
Default

Paper was difficult or not??????? but its not in line with previous paper pattern.....especially Bonding of CO via MOT was not an easy thing.....atleast for a BSC level student

Its also the fact that reading the Paper in CSS - Forum and saying it was easy is very easy but being in the paper situation lets you feel a bit different pressure.......

Sumyra is very respected member of CSS-Chemistry. She has qualified chemistry. Best luck to her.

CO via MOT was harsh and i could not do it in paper......Sumyra can u plz let me know its bonding? plz
Reply With Quote
  #10  
Old Sunday, March 11, 2012
sumyra's Avatar
40th CTP (OMG)
CSP Medal: Awarded to those Members of the forum who are serving CSP Officers - Issue reason: CE 2011 - Merit 174
 
Join Date: Sep 2010
Location: punjab
Posts: 124
Thanks: 118
Thanked 139 Times in 60 Posts
sumyra will become famous soon enoughsumyra will become famous soon enough
Default

Quote:
Originally Posted by Chintoo2010 View Post
Paper was difficult or not??????? but its not in line with previous paper pattern.....especially Bonding of CO via MOT was not an easy thing.....atleast for a BSC level student

Its also the fact that reading the Paper in CSS - Forum and saying it was easy is very easy but being in the paper situation lets you feel a bit different pressure.......

Sumyra is very respected member of CSS-Chemistry. She has qualified chemistry. Best luck to her.

CO via MOT was harsh and i could not do it in paper......Sumyra can u plz let me know its bonding? plz
i just read your post today and came to know that u have asked something from me..first of all thanx for appreciation..and secondly.. to say this question paper easy doesnt mean that we can attempt all the questions and it doesnt mean that i know each and every thing regarding chemistry.. i was just comparing this paper to the prvious year's because last year i was shocked to see the question paper .. i was able to attempt just 1 or 2 parts of each and every question in first paper...but this year chemistry first paper is a little bit different..atleast 4 required questions can be solved..
honestly speaking right now i dont know a b c of MOT it requires a lot of preparation and i always advise others not to opt chemistry.
i know the grievances of candidates opting chemistry because i am one of them
__________________
“The greatest barrier to success is the fear of failure.”
Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Judiciary Activism - A Timeline from NRO to Memograte (DAWN) umarbajwa Pakistan Affairs 0 Tuesday, March 13, 2012 08:22 PM
Middle east: Strategic impact of united states defence strategic review 2012 Shooting Star Current Affairs 0 Sunday, February 05, 2012 04:09 PM


CSS Forum on Facebook Follow CSS Forum on Twitter

Disclaimer: All messages made available as part of this discussion group (including any bulletin boards and chat rooms) and any opinions, advice, statements or other information contained in any messages posted or transmitted by any third party are the responsibility of the author of that message and not of CSSForum.com.pk (unless CSSForum.com.pk is specifically identified as the author of the message). The fact that a particular message is posted on or transmitted using this web site does not mean that CSSForum has endorsed that message in any way or verified the accuracy, completeness or usefulness of any message. We encourage visitors to the forum to report any objectionable message in site feedback. This forum is not monitored 24/7.

Sponsors: ArgusVision   vBulletin, Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.