BISE Lahore · Class 12 · Chemistry

BISE Lahore · Class 12 · Chemistry · 2025 · Group 2

2025

Transcribed from the identified examination paper. Check the board, session and course before use. SchoolOrbit is not affiliated with the issuing board.

Objective

Printed marks: 17 · Time: 20 Min.

OBJECTIVE

Q1(1)
Four possible answers A, B, C and D to each question are given. The choice which you think is correct, fill that circle in front of that question with Marker or Pen ink in the answer book. Cutting or filling two or more circles will result in zero mark in that question.
The reaction between fat and $N a O H$ is called:
- (A)
  Esterification
- (B)
  Hydrogenolysis
- (C)
  Fermentation
- (D)
  Saponification
Q1(2)
Four possible answers A, B, C and D to each question are given. The choice which you think is correct, fill that circle in front of that question with Marker or Pen ink in the answer book. Cutting or filling two or more circles will result in zero mark in that question.
$β, β^{'}$ -dichloroethyl Sulphide is commonly known as:
- (A)
  Mustard gas
- (B)
  Laughing gas
- (C)
  Phosgene gas
- (D)
  Bio-gas
Q1(3)
Four possible answers A, B, C and D to each question are given. The choice which you think is correct, fill that circle in front of that question with Marker or Pen ink in the answer book. Cutting or filling two or more circles will result in zero mark in that question.
Which is the strongest acid:
- (A)
  $H C l O$
- (B)
  $H C l O_{2}$
- (C)
  $H C l O_{3}$
- (D)
  $H C l O_{4}$
Q1(4)
Four possible answers A, B, C and D to each question are given. The choice which you think is correct, fill that circle in front of that question with Marker or Pen ink in the answer book. Cutting or filling two or more circles will result in zero mark in that question.
Ethanol can be converted into ethanoic acid by:
- (A)
  Hydrogenation
- (B)
  Hydration
- (C)
  Oxidation
- (D)
  Fermentation
Q1(5)
Four possible answers A, B, C and D to each question are given. The choice which you think is correct, fill that circle in front of that question with Marker or Pen ink in the answer book. Cutting or filling two or more circles will result in zero mark in that question.
Which of the following can be used as a catalyst in Friedel-Crafts reactions:
- (A)
  $A l C l_{3}$
- (B)
  $H N O_{3}$
- (C)
  $B e C l_{2}$
- (D)
  $N a C l$
Q1(6)
Four possible answers A, B, C and D to each question are given. The choice which you think is correct, fill that circle in front of that question with Marker or Pen ink in the answer book. Cutting or filling two or more circles will result in zero mark in that question.
Chile saltpetre has the chemical formula:
- (A)
  $N a N O_{3}$
- (B)
  $K N O_{2}$
- (C)
  $N a_{2} B_{4} O_{7}$
- (D)
  $N a_{2} C O_{3} . H_{2} O$
Q1(7)
Four possible answers A, B, C and D to each question are given. The choice which you think is correct, fill that circle in front of that question with Marker or Pen ink in the answer book. Cutting or filling two or more circles will result in zero mark in that question.
A single chloride free radical can destroy how many ozone molecules:
- (A)
  100
- (B)
  100,000
- (C)
  10,000
- (D)
  10
Q1(8)
Four possible answers A, B, C and D to each question are given. The choice which you think is correct, fill that circle in front of that question with Marker or Pen ink in the answer book. Cutting or filling two or more circles will result in zero mark in that question.
Co-ordination number of $P t$ in $[P t C l (N O_{2}) (N H_{3})_{4}]$ is:
- (A)
  2
- (B)
  4
- (C)
  1
- (D)
  6
Q1(9)
Four possible answers A, B, C and D to each question are given. The choice which you think is correct, fill that circle in front of that question with Marker or Pen ink in the answer book. Cutting or filling two or more circles will result in zero mark in that question.
Which of the following is not a fatty acid:
- (A)
  Propanoic acid
- (B)
  Acetic acid
- (C)
  Phthalic acid
- (D)
  Butanoic acid
Q1(10)
Four possible answers A, B, C and D to each question are given. The choice which you think is correct, fill that circle in front of that question with Marker or Pen ink in the answer book. Cutting or filling two or more circles will result in zero mark in that question.
Mark the correct statement:
- (A)
  Metallic character increases down the group
- (B)
  Metallic character increases from left to right along a period
- (C)
  Metallic character remains the same from left to right along a period
- (D)
  Metallic character remains the same down the group
Q1(11)
Four possible answers A, B, C and D to each question are given. The choice which you think is correct, fill that circle in front of that question with Marker or Pen ink in the answer book. Cutting or filling two or more circles will result in zero mark in that question.
When $C O_{2}$ is made to react with ethyl magnesium iodide, followed by acid hydrolysis, the product formed is:
- (A)
  Propane
- (B)
  Propanoic acid
- (C)
  Propanal
- (D)
  Propanol
Q1(12)
Four possible answers A, B, C and D to each question are given. The choice which you think is correct, fill that circle in front of that question with Marker or Pen ink in the answer book. Cutting or filling two or more circles will result in zero mark in that question.
Tincal is a mineral of:
- (A)
  $A l$
- (B)
  $B$
- (C)
  $S i$
- (D)
  $C$
Q1(13)
Four possible answers A, B, C and D to each question are given. The choice which you think is correct, fill that circle in front of that question with Marker or Pen ink in the answer book. Cutting or filling two or more circles will result in zero mark in that question.
For which crop, ammonium nitrate fertilizer is not used:
- (A)
  Cotton
- (B)
  Wheat
- (C)
  Sugarcane
- (D)
  Paddy rice
Q1(14)
Four possible answers A, B, C and D to each question are given. The choice which you think is correct, fill that circle in front of that question with Marker or Pen ink in the answer book. Cutting or filling two or more circles will result in zero mark in that question.
Cannizzaro’s reaction is not given by:
- (A)
  Formaldehyde
- (B)
  Acetaldehyde
- (C)
  Benzaldehyde
- (D)
  Trimethyl acetaldehyde
Q1(15)
Four possible answers A, B, C and D to each question are given. The choice which you think is correct, fill that circle in front of that question with Marker or Pen ink in the answer book. Cutting or filling two or more circles will result in zero mark in that question.
The pH range of the acid rain is:
- (A)
  7 – 6.5
- (B)
  6.5 – 6
- (C)
  6 – 5.6
- (D)
  Less than 5
Q1(16)
Four possible answers A, B, C and D to each question are given. The choice which you think is correct, fill that circle in front of that question with Marker or Pen ink in the answer book. Cutting or filling two or more circles will result in zero mark in that question.
Select from the following the one which is alcohol:
- (A)
  $C H_{3} C H_{2} O H$
- (B)
  $C H_{3} - O - C H_{3}$
- (C)
  $C H_{3} C O O H$
- (D)
  $C H_{3} - C H_{2} - B r$
Q1(17)
Four possible answers A, B, C and D to each question are given. The choice which you think is correct, fill that circle in front of that question with Marker or Pen ink in the answer book. Cutting or filling two or more circles will result in zero mark in that question.
Which of the following species has the maximum number of unpaired electrons:
- (A)
  $O_{2}$
- (B)
  $O_{2}^{+}$
- (C)
  $O_{2}^{-}$
- (D)
  $O_{2}^{2 -}$

Subjective

Printed marks: 68 · Time: 2.40 hrs.

SECTION-I

2
Write short answers to any EIGHT (8) questions:
Q2(i)
Define electron affinity. Give its trend within group and period of the periodic table.
Q2(ii)
What are halides? Give brief description of ionic halides.
Q2(iii)
Give two main points showing the difference of Beryllium from other 11A group elements.
Q2(iv)
Briefly explain the solubility of alkaline earth metal oxides in water.
Q2(v)
Briefly describe the functional group isomerism with at least two examples.
Q2(vi)
How is octane number of gasoline improved?
Q2(vii)
Write down the names of the following compounds according to IUPAC system: (a) $(C H_{3} C H_{2})_{3} C H$ (b) $(C H_{3})_{2} C = C H_{2}$
Q2(viii)
Give reactions showing the regeneration of acetylene from copper and silver acetylides.
Q2(ix)
What is the difference between ortho-para and meta directing groups?
Q2(x)
How is benzoic acid prepared from methyl and ethyl benzene?
Q2(xi)
How is n-Butane prepared through Wurtz Synthesis?
Q2(xii)
How is 1-Butanol prepared from ethyl magnesium bromide?
3
Write short answers to any EIGHT (8) questions:
Q3(i)
Complete and balance the following chemical equations: (a) $H N O_{3} + H I ⟶$ (b) $P + N O ⟶$
Q3(ii)
Give the reaction of $H_{2} S O_{4}$ (conc.) with: (a) $C_{(s)}$ (b) $S_{(s)}$
Q3(iii)
Why is $C O_{2}$ gas at room temperature while $S i O_{2}$ , is a solid?
Q3(iv)
Outline principal uses of borax.
Q3(v)
How will you differentiate chemically between methyl alcohol and ethyl alcohol? Give reactions.
Q3(vi)
Give the reaction of diethyl ether with HI.
Q3(vii)
What is the Tollen’s test? Give its importance.
Q3(viii)
Give any four uses of acetaldehyde.
Q3(ix)
Write down formulas of palmitic acid and stearic acid.
Q3(x)
How does carboxylic acids react with carbonate and bicarbonate? Give reactions.
Q3(xi)
What is iodine number? Give its importance.
Q3(xii)
Briefly discuss the importance of enzymes (Any Two).
4
Write short answers to any SIX (6) questions:
Q4(i)
Iodine is very important for pharmaceutical industry, give reason.
Q4(ii)
Write two methods for the preparation of xenon oxyfluorides.
Q4(iii)
Why d block elements show variable valency/oxidation states?
Q4(iv)
Write chemistry of chromyl chloride test.
Q4(v)
What is the meaning of setting of cement?
Q4(vi)
Write screening process in paper industry.
Q4(vii)
Atmosphere maintain heat balance of earth, justify.
Q4(viii)
Oil spillage affects the marine life, justify.
Q4(ix)
What is the role of ozone in atmosphere?

SECTION-II

Note: Attempt any THREE questions.

Q5
(8 marks)
1. (a)
  How do you justify the position of hydrogen at the top of group I A and group IV A?
  (4 marks)
2. (b)
  What is the role of lime in industries? Mention any eight (8) points.
  (4 marks)
Q6
(8 marks)
1. (a)
  What are the types of structural isomerism? Explain any four types.
  (4 marks)
2. (b)
  Explain with Mechanism Sulphonation of Benzene.
  (4 marks)
Q7
(8 marks)
1. (a)
  Write the reactions of ethene with the following: (i) $H B r$ (ii) $B r_{2}$ (iii) $O_{3}$ (iv) $H O C l$
  (4 marks)
2. (b)
  Discuss the reaction of ethanal and propanone with: (i) Phenyl hydrazine. (ii) Hydroxylamine.
  (4 marks)
Q8
(8 marks)
1. (a)
  How ethanol prepared from: (i) Molasses. (ii) Starch.
  (4 marks)
2. (b)
  Discuss the mechanism for following conversions: (i) Acetic acid into ammonia. (ii) Acetic acid into ethanol.
  (4 marks)
Q9
(8 marks)
1. (a)
  Explain the preparation of bleaching powder by Beckmann’s method with diagram.
  (4 marks)
2. (b)
  Define with one example the following term: (i) Ligands. (ii) Co-ordination sphere. (iii) Substitutional alloy. (iv) Central metal atom.
  (4 marks)

Original source references (2)

The original files and numbering are retained. Equivalent files do not repeat the questions above.

Objective · psp_0ba142f7df52366af0d26c765bc8142e · Printed marks: 17 · Time: 20 Min.
Subjective · psp_a73a6439f30f18a67d7d54f10e1cf0f5 · Printed marks: 68 · Time: 2.40 hrs.