PSEB CLASS 12 CHEMISTRY QUESTION PAPER PDF WITH ANSWER KEY DOWNLOAD HERE
- (i) Questions no. 1 has 28 sub-parts and each carries one mark.
- (ii) Questions no. 2 to 11 carry two marks. All questions are compulsory.
- (iii) Questions no. 12 to 15 carry three marks . All questions are compulsory.
- (iv) Questions no. 16 and 17 carry five marks. All questions are compulsory. There is internal choice in them.
Question 1
Which of the following reagent is used as a refrigerant?
(a) CCL₄ (b) CH₂Cl₂ (c) CF₂Cl₂ Correct (d) CF₄
Question 2
Phenol on distillation with Zinc dust gives:
(a) Benzene Correct (b) Benzaldehyde (c) Benzoic Acid (d) Benzophenone
Question 3
Which of the following is strongest acid?
(a) CH₃COOH (b) CH₃CHClCOOH Correct (c) CH₃CH₂COOH (d) ClCH₂COOH
Question 4
In the carbonyl group the carbon atom undergoes:
(a) sp Hybridisation (b) sp² Hybridisation Correct (c) sp³ Hybridisation (d) sp³d Hybridisation
Question 5
Williamson synthesis is used to prepare:
(a) Alcohol (b) Amine (c) Ketone (d) Ether Correct
Question 6
Ethers on hydrolysis give:
(a) Carboxylic acid (b) Alcohol Correct (c) Ester (d) Ketone
Question 7
Which of the following is hexadentate ligand?
(a) Diene (b) CN⁻ (c) en (d) EDTA Correct
Question 8
What is oxidation state of Fe in K₃[Fe(CN)₆]?
(a) +2 (b) +3 Correct (c) +4 (d) +1
Sure, I can write the MCQs and identify the correct answers from the image you sent.
IX. The correct IUPAC name of [PVH3)2Cl2] is:
(a) Diammine dichlorido platinum (II) (Correct) (b) Diammine dichloride platinum (IV) (c) Diammine dichlorido platinum (0) (d) Diammine chloride platinum (IV)
X. In [x(NH3)4Cl2] the ligands are:
(a) NH3 only (b) Cl-1 only (c) Both NH3 and Cl-1 (Correct) (d) Cl2, NH3
XI. The metal used for galvanization of iron is:
(a) Magnesium (b) Zinc (Correct) (c) Copper (d) None of those
XII. The number of reacting species which collide simultaneously to bring about a chemical reaction is called:
(a) Molecularity (Correct) (b) Order of reaction (c) Rate of reaction (d) None of these
XIII. Units of rate constant for zero order reaction is:
(a) Sec-1 (b) mol L-1 sec-1 (Correct) (c) mol-1 L2 sec-1 (d) mol-1L sec-1
XIV. When initial concentration of the reactant is doubled the half life period of a zero order reaction is:
(a) Halved (b) Doubled (Correct) (c) Unchanged (d) None of these
XV. Carbon dioxide dissolved in water is an example of:
(a) Gas in gas (b) Solid in solid (c) Gas in liquid (Correct) (d) Gas in solid
XVI. The concentration term independent of temperature is:
(a) Normality (b) Mass volume percentage (c) Molarity (d) Molality (Correct)
XVII. What is normality of 1.0 M NaOH?
(a) 2N (b) 1N (Correct)(c) 3 N (d) 4 N
XVIII. The units of conductivity are:
(a) ohm-1 cm-1 (Correct) (b) ohm-1 cm² (c) ohm-1 (d) ohm2cm2 equiv -1░
(xix) Formic acid is obtained from red ants. [True/False]
Answer: True
(xx) Amines Act as Lewis Base.
Answer: True
(xxi) The formula of Benzene diazonium chloride is C6H5N2+Cl-1
Answer: False. The formula of Benzene diazonium chloride is C6H5N₂+ Cl⁻.
(xxii) Oxidation takes place at the anode in an electrolytic cell.
Answer: True
(xxiii) K4[Fe(CN)4] is a double salt.
Answer: False
Passage:
It has been observed that certain organic compounds are required in small amounts in our diet but their deficiency causes specific diseases. These compounds are called vitamins. They are generally regarded as organic compounds required in the diet in small amounts to perform specific biological functions for normal maintenance of optimum growth health of the organism. Vitamins are designated by alphabets A, B, C, D etc. Some of them are further named as sub-groups. Fat soluble vitamins: Vitamins are soluble in fat and oils but insoluble in water are kept in this group. These are vitamins A, D, E and K. Water soluble vitamins: B group vitamins and vitamin C are soluble in water so they are grouped together. Water soluble vitamins must be supplied regularly in diet because they are readily excreted in urine and cannot be stored in our body. Vitamin H is not soluble in fat nor in water.
Questions and Answers:
(sodv) Which vitamins are water soluble?
Answer: B group vitamins and vitamin C [based on the passage]
(xv) Which vitamins are fat soluble?
Answer: Vitamins A, D, E and K [based on the passage]
(xxvi) Which vitamins are not soluble in fat or water?
Answer: Vitamin H [based on the passage]
(xxvii) What are Vitamins?
Answer: Organic compounds required in small amounts in our diet to perform specific biological functions for normal maintenance of optimum growth health of the organism [based on the passage]
(xxxviii) How many types of Vitamins?
Answer: Mention two categories: fat-soluble and water-soluble [based on the passage] ░
2. The half-life period of a chemical reaction is 1626 sec. Find the specific rate constant (K) for this reaction.
OR
Find the half-life period of a first-order reaction whose rate constant (K) is 4.93×10^-4 sec^-1.
3. Give two differences between a double salt and a coordination compound.
4. Why do alcohols have higher boiling points than haloalkanes of the same molecular mass?
OR
Why are alcohols weaker acids than water?
5. Why are aldehydes more reactive than ketones?
OR
How will you distinguish between benzaldehyde and acetophenone?
6.La(OH)3 is more basic than Lu(OH)3. Explain.
7.Which is more basic, aliphatic amines or ammonia, and why?
8. Give two differences between DNA and RNA
9. Give two differences between Osmosis and Diffusion
10. Find the molarity if 0.0590 moles of compound dissolved in 500 ml of its solution . OR
Calculate the boiling point of solution when 2 gm of Na2SO4 (M=142g mol-1) was dissolved in 50 gm of water assuming Na2SO4 undergoes complete ionization. (Kb for water = 0.52 K kg mol-1)
11. Calculate the Eᵒcell⁰ from the given value: E⁰(Cu2+/Cu) = 0.34 V E⁰(Zn2+/Zn) = 0.76 V Also, tell can you store copper sulphate in Zinc pot?
Three marks questions
12. 60% of a first order reaction was completed in 60 min when was it half completed?
13. Write vector Meyer's test for 1° 2° and 3° alcohols.
OR
(a) Why are ethers are relatively inert compounds?
(b) Write Reimer - Tiemanns reaction.
14. (a) Why are aryldiazonium ion more stable than alkyldiazonium ion?
(b) Why are lower amine soluble in water?
15. Calculate the molar conductance at infinite dilution for acetic acid, given: Λ(HCl) = 425 ohm cm² mol-1 Λm(NaCl) = 188 ohm^-1cm² mol^-1 Λ(CH3COONa) = 96 ohm cm² mol-1
OR
Calculate the standard electrode potential of Ni +2/Ni electrode if the cell potential of the cell Ni/Ni +2 (0.01 M) || Cu +2 (0.1 M)/Cu is 0.59 V given E⁰(Cu2+/Cu) = 0.34 V.
Sure, based on the image you sent, here are questions 16 and 17 with all options:
16. (a) Write the following reaction:
(i) Sandmeyer's reaction
(ii) Ullmann reaction
(iii) Friedel-Crafts alkylation reaction
(b)
(i)Convert the following: Benzene to chlorobenzene
(ii) Bromobenzene to Diphenyl
OR
(a) Give three differences between S1 (Substitution nucleophilic unimolecular reaction) and S2 (Substitution nucleophilic bimolecular reaction).
(b) Why solubility of Haloalkanes in water is very low? 2
**17. (a) Give three differences between Lanthanoids and Actinoids. 3+2=5
(b) Why transition element forms coloured compounds? Explain.
OR
**(a) Write three similarities between Lanthanoids and Actinoids. 3+2=5
(b) What is lanthanoid contraction? ░
PSEB 12 CLASS CHEMISTRY QUESTION PAPER 2024 WITH ANSWER KEY DOWNLOAD HERE
