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PART: A
Multiple Choice Type Questions
Question number 1 to 25 are multiple choice type. Each questions has four options. Select the correct options and write it in the answer sheet. Each question carries one mark. 1 × 25 = 25
1. Which of the following aqueous solutions should have the highest boiling point?
a) 1.0 M NaOH
b) 1.0 M Na2SO4
c) 1.0 M NH4NO3
d) 1.0 M KNO3
View Answer
1.0 M Na2SO4.
Elevation in boiling point depends on the number of solute particles (ions) produced in solution (i.e., its van't Hoff factor, i).
Na2SO4 dissociates into three ions (2 Na⁺ and 1 SO42-), yielding the highest total ion concentration compared to the other salts given, leading to the largest colligative effect and the highest boiling point.
2. An example of colligative property of solution is
a) density
b) mass
c) elevation of boiling point
d) temperature
View Answer
elevation of boiling point.
3. What is the molarity of a solution with a mass of solute 10 kg and 100 litre volume?
a) 0.1 molar
b) 1 molar
c) 10 molar
d) 100 molar
View Answer
0.1 molar.
Number of moles of solute = 10kg/1kg per mol = 10 moles
Volume of the solution is given as 100 liters.
Molarity of the solution = 10/100 = 0.1M
4. The unit of molar conductivity is
a) S cm-2mol-1
b) S cm2mol-1
c) S-1cm2mol-1
d) S cm2mol
View Answer
S cm2mol-1.
5. The amount of electricity required to obtain one mole of Zn from ZnSO4 solution will be
a) 3F
b) 4F
c) 1F
d) 2F
View Answer
2F.
Zn2+ + 2e- → Zn
1 mole of Zn2+ requires 2 moles of electrons to form 1 mole of Zn.
Since 1 Faraday (1F) is the charge of 1 mole of electrons so, 2 moles of electrons correspond to 2F.
Therefore, The amount of electricity required to obtain one mole of Zn from ZnSO4 solution is 2F.
6. The unit of rate constant for the reaction
2H2 + 2NO → 2H2O + N2
which has rate R = K[H2] [NO]2 is
a) mol L-1 s-1
b) s-1
c) mol-2 L2 s-1
d) mol L-1
View Answer
mol-2 L2 s-1.
k = rate [H₂] [NO]²
or, k = mol L⁻¹ s⁻¹ / (mol L⁻¹)(mol L⁻¹)²
or, k = mol⁻² L² s⁻¹
7. What is the concentration of the reactant in a first order reaction, when the rate of the reaction is 0.6 Ms-1 and the rate constant is 0.035 s-1?
a) 26.667 M
b) 17.143 M
c) 26.183 M
d) 17.667 M
View Answer
17.143 M.
Rate = k[A]
or, k = Rate /[A]
or, k = 0.6/0.035 = 17.143 M
8. Which of the following represents Arrhenius equation?
a) k = AeEa/RT
b) k = Ae-Ea/RT
c) k = AeEa/R
d) dk = AeEa/T
View Answer
k = Ae-Ea/RT.
9. Which of the following is a diamagnetic ion?
a) V2+
b) Sc3+
c) Cu2+
d) Mn3+
View Answer
Sc3+.
V2+ has 3 unpaired electrons in its d-orbitals.
Sc3+ has no unpaired electron.
Cu2+ has one unpaired electron.
Mn3+ has four unpaired electrons.
Ions having no unpaired electron are diamagnetic.
10. Which property of transition metals enables them to behave as catalysts?
a) High melting point
b) High ionisation enthalpy
c) Alloy formation
d) Variable oxidation state
View Answer
Variable oxidation state.
11. Oxidation state of Cu in [Cu(NH3)4]2+ is
a) -2
b) +4
c) +2
d) 0
View Answer
+2.
12. dsp2 hybridisation is present in
a) [Ni(CO)4]
b) [Ni(CN)4]2-
c) [Cu(NH3)4]2+
d) [MnCl4]2-
View Answer
[Ni(CN)4]2-.
13. What is the IUPAC name of the following compound?
CH3-CH=CH-CH2-Br
a) 1-Bromo-3-methyl prop-2-ene
b) 3-Bromo-1-methyl propene
c) 1-Bromobut-2-ene
d) 4-Bromobut-2-ene
View Answer
1-Bromobut-2-ene.
14. In which medium does Finkelstein reaction take place?
a) Concentrated HCl
b) Concentrated H2SO4
c) Dry acetone
d) Water
View Answer
Dry acetone.
Finkelstein Reaction: Alkyl chloride or bromide converted into an alkyl iodide by reacting with sodium iodide in a polar aprotic solvent like acetone.
15. The test used to distinguish between primary, secondary and tertiary alcohol is
a) Tollen's test
b) Lucas test
c) Fehling's test
d) Hinsberg's test
View Answer
Lucas test.
Tollen's Test: Distinguish between reducing and non-reducing sugars
Lucas Test: Distinguish among primary, secondary, and tertiary alcohols
Fehling Test: Detect reducing sugars
Hinsberg's Test: Distinguish among primary, secondary, and tertiary amines.
16. Ethyl alcohol ---Cu/573K→ A, 'A' is
a) Acetaldehyde
b) Propionaldehyde
c) Acetone
d) Ethanoic acid
View Answer
Acetaldehyde.
17. Which reaction is used for the preparation of symmetric and asymmetric ethers?
a) Finkelstein reaction
b) Reimer-Tiemann reaction
c) Williamson synthesis
d) Etard reaction
View Answer
Williamson synthesis.
18. Oxidation of propan-1-ol with alkaline KMnO4 solution gives
a) propanoic acid
b) propane
c) ethane
d) propanal
View Answer
propanoic acid.
19. The reaction
C6H5-OH + CHCl3 + KOH ---△ → Salicylaldehyde
is
a) Gattermann-Koch reaction
b) Sandmeyer reaction
c) Reimer-Tiemann reaction
d) Fittig reaction
View Answer
Reimer-Tiemann reaction.
Reimer-Tiemann Reaction: A formyl group is introduced at ortho position in phenol when it reacts with chloroform in the presence of aqueous KOH.
20. What is the relation between acidic strength of A and B?
A) p-methoxy benzoic acid
B) p-nitro benzoic acid
a) A = B
b) A > B
c) A < B
d) A >> B
View Answer
A < B.
The nitro group (-NO2) is an electron-withdrawing group that pulls electrons away from the carboxyl group, making it easier to release a proton and thus increasing the acidity.
However, The methoxy group (-OCH3) is an electron-donating group that pushes electrons towards the carboxyl group, making it harder to release a proton and decreasing the acidity.
21. C6H5CONH2 + Br2 + 4NaOH → Product, Product is
a) C6H5COOH
b) C6H5NC
c) C6H5NH2
d) C6H6
View Answer
C6H5NH2.
Hofmann Bromamide Reaction:
C6H5CONH2 + Br2 + 4NaOH → C6H5NH2 + Na2CO3 + 2NaBr + 2H2O
22. The test which is used to distinguish between primary amine and secondary amine is
a) Lucas test
b) Carbylamine test
c) Fehling's test
d) Tollen's test
View Answer
Carbylamine test.
The Carbylamine test reacts with primary amines to produce a foul-smelling isocyanide, while secondary amines do not react in the same way.
23. Which of the following monosaccharides is a ketohexose?
a) Glucose
b) Galactose
c) Fructose
d) Mannose
View Answer
Fructose.
24. Identify the complementary strand of the DNA primary structure ATGCCGATC.
a) AUGCCGAUC
b) TACGGCJAG
c) UACGGCUAG
d) GATCGGCAT
View Answer
TACGGCATC.
25. Retinol is vitamin
a) A
b) C
c) D
d) K
View Answer
A.