SAHIWAL BOARD 2013
PAPER CHEMISTRY PART-II
Time: 20 Min
(Objective Part)
Marks: 17
Note: Four answer are given against each question in columns A,B,C and D. Select the right answer and on the separate Answer Sheet, fill the circle A,B,C or D with pen or marker in front of that question number.

Question#1

• Which one of the following elements forms amphoteric oxide.
  
  (a) Ca
  (b) Fe
  (c) S
  (d)Zn
  
  
• Carmalite is the mineral of:
  
  (a) Be
  (b) Na
  (c) Mg
  (d) Ca
  
  
• Boric acid can not be used:
  
  (a) An antiseptic in medicine
  (b) For washing eyes
  (c) In soda bottles
  (d) For enamles and glazes
  
  
• The brown gas formed, when metal reduces HNO₃ to:
  
  (a) N₂0₅
  (b) N₂0₃
  (c) NO₂
  (d) NO
  
  
• Which of the following hydrogen halide is the weakest acid in solution?
  
  (a) HF
  (b) HBr
  (c) HI
  (d) HCI
  
  
• Coordination number of pt in [PtCl(NO₂)(NH₃)₄]²⁺ is:
  
  (a) 2 -
  (b) 4
  (c) 1
  (d) 6
  
  
• Linear shape is associated with which set of hybrid orbital?
  
  (a) Sp
  (b) sp²
  (c) sp³
  (d) dsp ²
  
  
• The addition of unsymmetrical reagent to an unsymmetrical alkene is in accordance with the rule:
  
  (a) H.und's rule
  (b) Markownikov's rule
  (c) Pauli's Exclusion Principle
  (d) Autbau Principle
  
  
• Which compound is the most reactive one
  
  (a) Benzee
  (b) Ethene
  (c) Ethane
  (d) Ethyne
  
  
• When CO₂ is made to react with ethyl magnesium iodide, followed by acid hydrolysis, the product is:
  
  (a) Propane
  (b) Propanc acid r
  (c) Propanal
  (d) Propanol
  
  
• Which compound shows maximum hydrogen bonding with water?
  
  (a) C₃H₇OH
  (b) C₂H₅ OH
  (c) CH₃-O–CH₃
  (d) C₆H₅OH
  
  
• Which of the following compounds will not give iodoform test on treatment with l_/2 NaOH?
  
  (a) Acetaldehyde
  (b) Acetone
  (c) Butanone
  (d) 3-pentanone
  
  
• The carbon atom of a carbonyl group is:
  
  (a) sp hybridized
  (b) Sp² hybridized
  (c) Sp³ hybridized
  (d) dsp² hybridized
  
  
• Which of the following in not a fatty acid:
  
  (a) Propanoic acid
  (b) Acetic acid
  (c) Phthalic acid
  (d) Butannic acid
  
  
• Which of the following elements is not present in all proteins?
  
  (a) Carbon
  (b) Hydrogen
  (c) Nitrogen
  (d) Sulphur
  
  
• Which is not calcarious material?
  
  (a) Lime
  (b) Clay
  (c) Marble
  (d) Marine shell
  
  
• Ecosystem is a smaller unit of:
  
  (a) Lithosphere
  (b) Hydrosphere
  (c) Atmosphere
  (d) Biosphere

Time: 3:10 Hours
(Subjective Part)
Marks: 83
Section II

2. Attempt any EIGHT short questions. (8x2=16)

• How the classification of elements in different blocks help in understanding chemistry.
• Why ionization energy decreases down the group. Given reason.
• Write the advantages of Nelson cell.
• What is the role of gypsum in agriculture?
• Write a brief note not he occurrence of alkaline earth metals.
• Complete the following reactions:
• (a) HNO₃ con. +H₂S→
  (b) HNO₃con. +Hl→
• Write the four applications of H₂SO₄.
• Write the chemical reactions which take place in contact chamber.
• What is peculiar behavior of Fluorine.
• What Id d - d transition explain it with respect to [Ti (H₂O)₆ ]³⁺
• How ethane can be prepared by koib's electrolysis.
• Explain the acidic nature of ethyne.

3. Attempt any EIGHT short questions. (8x2-16)

• Give equations to represent the following reactions:
  (a) Borax is heated with C0O (cobalt oxide).
  (b) Al₂O₃ is heated with NaOH.
• Write short note on white LEAD and LEAD chromate.
• Write types of bonds and shapes of HCHO and CH₃Cl using bygridization approach.
• Write a brief note on geometric isomerism.
• Write down nitration and sulphonation of benzene.
• Write down structure formulas of (a) O-Xylene (b) 4-amino phenol.
• How can you convert the following?
  (a) CH₃=CH₃→CH₃–CH₃–CH₃-CH₃--OH
  (b) CH₃– CH₂–CH₂–ClCH₃ –CH=CH₂
  
• Write a brief note on R-Mg-X.
• Write a note on Lucas test.
• How can you prepare Ethers:
• What do you know about structure of amino acids.
• Write down mechanism of reactions.
• Between acetic acid and ethanol
• Acetic acid and thionyl chloride.

4. Attempt any SIX short questions. (6x2=12)

• Fehling's solution reacts with aldehydes to give red ppt. justify it.
• Give reaction to produce a– Hydroxy acid from aldehyde.
• Justify that Cannizzaro’s reaction is self oxidation - reduction reaction.
• Addition of HCN on aldehydes and ketones is a base catalyzed reaction.
• What do you mean by the rancidity oils and fats?
• Write any two differences between DNA and RNA.
• Give the important qualities of fertilizer.
• Give an idea about clinker.
• What are the conditions for the formation of smog?

SECTION-III

Attempt any, THREE questions (8x3=24)
Question#5
(a) What are hydrides? How these are classified. Also give their physical properties. (2+2)
(b) Complete and balancing the following equations. (0+4)
(i) KO₂ CO₂→
(ii) Mg₃ N₂+ H₂O →
(iii) Na₂O₂+H₂O →
(iv) BeO +NaOH→

Question#6
(a) Explain sp3 hybridization. How it explains the structure of methane? (4)
(b) Discuss reduction of carbonyl compounds with sodium borohydride with proper mechanism. (1+3)

Question#7
(a) Write a note on polymerization of ethyne. (4)
(b)Differentiate between S v' and S,' reaction mechanism. (4)

Question#8
(a) How benzene is prepared from cyclohexane, Acetylene alkanes.
(b) Write down any four methods for preparation of carbosylic acids. (3+1)

Question#9
(a) How wrought iron is manufactured from cast iron.  (4)
(b)How water is made potable by aeration and coagulation. (4)