Question Bank for Chemistry in Engineering Entrance standard : Just Exam

1. Some Basic Concepts of Chemistry - Quiz

1. What volume of hydrogen gas, at 273 K and 1 atm pressure will be consumed in obtaining 21.6 g of elemental boron (atomic mass = 10.8) from the reduction of boron trichloride by hydrogen ?
a) 89.6 L
b) 67.2L
c) 44.8 L
d) 22.4 L

2. A gaseous hydrocarbon gives upon combustion, 0.72 g of water and 3.08 g of CO₂. The empirical formula of the hydrocarbon is:
a) C₂H₄
b) C₃H₄
c) C₆H₅
d) C₇H₈

2. States of Matter - Quiz

1. Lithium forms body-centered cubic structure. The length of the side of units cell is 351 pm. Atomic radius of the lithium will be
a) 75 pm
b) 300 pm
c) 240 pm
d) 152 pm

2. For gaseous state, if most probable speed is denoted by C*, average by $\overline{C}$ and mean square speed by C, then for a large number of molecules, the ratio of these speeds are
a) C* : $\overline{C}$ : C = 1.225 : 1.128 : 1
b) C* : $\overline{C}$ : C = 1.128 : 1.225 : 1
c) C* : $\overline{C}$ : C = 1 : 1.128 : 1.225
d) C* : $\overline{C}$ : C = 1 : 1.225 : 1.128

3. Atomic Structure - Quiz

1. In an atom, an electron is moving with a speed of 600m/s with an accuracy of 0.005%. Certainity with which the position of the electron can be located is (h = 6.6 × 10^-34 kg m²s^-1, mass of electrons, em = 9.1 × 10^-31 kg
a) 1.52 × 10^-4 m
b) 5.10 × 10^-3 m
c) 1.92 × 10^-3 m
d) 3.84 × 10^-3 m

2. Ionisation energy of He⁺ is 1.96× 10^-18 J atom^-1 . The energy of the first stationary state (n=1) of Li²⁺ is
a) 4.41 × 10^-16 J atom^-1
b) -4.41 × 10^-17 aJ atom^-1
c) -2.2 × 10^-15 J atom^-1
d) 8.82× 10^-17 J atom^-1

4. Chemical Bonding - Quiz

1. Hybridisation of the underline atom changes in
a) $\underline{Al}H_{3}$ changes to $AlH_{4}^{-}$
b) $H_{2}\underline{O}$ changes to $H_{3}O^{+}$
c) $\underline{N}H_{3}$ changes to $NH_{4}^{+}$
d) In all cases

2. The correct order of bond angles (smallest first) in H₂S, NH₃, BF₃ and SiH₄ is
a) H₂S < SiH₄ < NH₃ < BF3
b) NH₃ < H₂S < SiH₄ < BF₃
c) H₂S < NH₃ < SiH₄ < BF₃
d) H₂S < NH₃ < BF₃ < SiH₄

5. Thermodynamics - Quiz

1. The correct relationship between free energy change in a reaction and the corresponding rquilibrium constant K is
a) ΔG = RT ln K_c
b) -ΔG = RT ln K_c
c) ΔG⁰ = RT ln K_c
d) -ΔG⁰ = RT ln K_c

2. Standard entropy of X₂, Y₂ and XY₃ are 60, 40 and 50 JK^-1 mol^-1, respectively. For the reaction,
$\frac{1}{2}X_{2} + \frac{3}{2}Y_{2} → XY_{3} , \Delta H$ = -30kJ, to be at equilibrium, the temperature will be
a) 1250 K
b) 500 K
c) 750 K
d) 1000 K

6. Solutions - Quiz

1. Which one of the following statements is false?
a) Raoults law states that the vapour pressure of a component over a solution is proportional to its mole fraction
b) The osmotic pressure (π) of a solution is given by the equation π = MRT , where M is the molarity of the solution
c) The correct order of osmotic pressure for 0.01 M aqueous solution of each compound is BaCl₂ > KCl > CH₃COOH > sucrose
d) Two source solutions of same molality prepared in different solvents will have the same freezing point depression

2. Equal masses of methane and oxygen are mixed in an empty container at 25⁰ C. the fraction of the total pressure exerted by oxygen is
a) $\frac{2}{3}$
b) $\frac{1}{3} \times \frac{273}{298}$
c) $\frac{1}{3}$
d) $\frac{1}{2}$

7. Equilibrium - Quiz

1. The equilibrium constant (K_c) for the reaction N₂(g) + O₂(g) → 2NO (g) at temperature T is 4 x 10^-4.
The value of K_c for the reaction NO(g) → $\frac{1}{2}$N₂(g) + $\frac{1}{2}$O₂(g) at the same temperature is
a) 0.02
b) 2.5 × 10²
c) 4 x 10^-4
d) 50.0

2. In aqueous solution, the ionisation constants for carbonic acid are
k₁ = 4.2 x 10^-7 and K₂ = 4.8 x 10^-11
Select the correct statement for a saturated 0.034 M solution of the carbonic acid.
a) The concentration of $CO_{3}^{2-}$ is 0.034 M
b) The concentration of $CO_{3}^{2-}$ is greater than that of $HCO_{3}^{-}$
c) The concentration of H⁺ and $HCO_{3}^{-}$ are approximately equal
d) The concentration of H⁺ is double that $CO_{3}^{2-}$

8. Redox Reactions and Electrochemistry - Quiz

1. Resistance of 0.2M solution of an electrolyte is 50Ω . The specific conductance of the solution is 1.3 Sm^-1. If resistance of the 0.4M solution of the same electrolyte is 260 Ω its molar conductivity is
a) 6250 S m² mol^-1
b) 6.25 × 10^-4 Sm² mol^-1
c) 625 × 10^-4 S m² mol^-
d) 62.5 S m² mol^-1

2. In which of the following reactions H₂O₂ acts as a reducing agent?
1. H₂O₂ + 2H⁺ + 2e^- → 2H₂O
2. H₂O₂ - 2e^- → O₂ + 2H⁺
3. H₂O₂ + 2e^- → 2OH^-
4. H₂O₂ + 2OH^- - 2e^- → O₂ + 2H₂O
a) 1,2
b) 3,4
c) 1,3
d) 2,4

9. Chemical Kinetics and Surface Chemistry - Quiz

1. Rate constant , k of the first order reaction when initial concentration (C₀) and concentration (C_t) at time t, is given by equation kt = log C₀ - log C_t
Graph is a straight line if we plot
a) t vs log C₀
b) t vs log C_r
c) t^-1 vs log C_r
d) log C₀ vs log C_r

2. The rate of a chemical reaction doubles for every 10⁰C rise of temperature. If the temperature is raised increases by 50⁰C, the rate of the reaction increases by about
a) 10 times
b) 24 times
c) 32 times
d) 64 times

10. Periodicity of Elements - Quiz

1. The increasing order of the first ionisation enthalpies of the elements B,P,S and F (lowest first) is
a) F < S < P < B
b) P < S < B < H
c) B < P < S < F
d) B < S < P < F

2. Which among the following factors is the most important in making fluorine the strongest oxidising agent?
a) Electron affinity
b) Ionisation enthalpy
c) Hydration enthalpy
d) Bond dissociation energy

11. Principles and Processes of Metallurgy - Quiz

1. Aluminium is extracted by the electrolysis of
a) alumina
b) bauxite
c) molten cryolite
d) alumina mixed with molten cryolite

2. Refining of impure copper with zinc impurity is to be done electrolysis using electrodes as
a) cathode - pure copper, Anode - pure zinc
b) cathode - pure zinc, Anode - copper
c) cathode - pure copper, Anode - impure copper
d) cathode - pure zinc, Anode - impure zinc

12. Hydrogen, s and p-Block Elements - Quiz

1. Among the following oxoacids, the correct decreasing order of acid strength is
a) HOCL > HClO₂ > HClO₃ > HClO₄
b) HClO₄ > HOCl > HClO₂ > HClO₃
c) HClO₄ > HClO₃ > GClO₂ > HOCl
d) HClO₂ > HClO₄ > HClO₃ > HOCl

2. The solubilities of carbonates decraese down the magnesium group due to a decrease in
a) lattice energies of solids
b) hydration energies of cations
c) inter ionic attraction
d) entropy of solution formation

13. d- and f-Block Elements and Coordination Chemistry - Quiz

1. Which one of the following has largest number of isomers?
a) [Ru(NH₃)₄Cl₂]⁺
b) [Co(NH₃)₅Cl]²⁺
c) [Ir(PR₃)₂H(CO)]²⁺
d) [Co(en)2Cl2]+

2. The value of the spin only magnetic moment for one of the following configuration is 2.84BM. The correct one is
a) d⁵ (in strong ligand field)
b) d³ (weak as well as in strong fields
c) d⁴ ( in weak ligand field)
d) d4 (in strong ligand field)

14. Environmental Chemistry - Quiz

1. The gas leaked from a storage tank of the Union Carbide plant in Bhopal gas tragedy was
a) Methylisocyanate
b) Methylamine
c) Ammonia
d) Phosgene

2. The smog is essentially caused by the presence of
a) O₂ and O₃
b) O₂ and N₂
c) oxides of sulphur and nitrogen
d) O₃ and N₂

15. General Organic Chemistry - Quiz

1. Among the following acids which has the lowest pK_a value?
a) CH₃CH₂COOH
b) (CH₃)₂CH-COOH
c) HCOOH
d) CH₃COOH

2. The correct decreasing order of priority for the functional groups of organic compounds in the IUPAC system of nomenclature is
a) -COOH, -SO₃H, -CONH₂, -CHO
b) -SO₃H, -COOH, -CONH₂, -CHO
c) -CHO, -COOH, -SO₃H, -CONH₂
d) -CONH₂, -CHO, -SO₂H, -COOH

16. Hydrocarbons and their Halogen Derivatives - Quiz

1. The reaction of solute of toulene with Cl₂ in presence of FeCl₃ gives predominantly
a) benzyl chloride
b) benzyl chloride
c) o - and p - chlorotoulene
d) m-chlorotoulene

2. The compound formed on heating chlorobenzene with chloral in the presence of concentrated sulphuric acid is
a) gammexane
b) DDT
c) freon
d) hexachloroethane

17. Organic Compounds Containing Oxygen - Quiz

1. An unknown alcohol is treated with the Lucas reagent to determine whether the alcohol is primary , secondary or tertiary. Which alcohol reacts fastest and by what mechanism?
a) Secondary alcohol by S_N 1
b) Tertiary alcohol by S_N 1
c) Secondary alcohol by S_N 2
d) Tertiary alcohol by S_N 2

2. The correct order of acid strength of the following compounds is
I. Phenol. II. p-cresol
III. m-nitrophenol. IV. p-nitrophenol
a) III > II > I > IV
b) IV > III > I > II
c) Ii > IV > I > III
d) I > II > IV > III

18. Organic Compounds Containing Nitrogen - Quiz

1. Reaction of cyclohexane with dimethylamine in the presence of catalytic amount of an acid forms a compound . Water during the reaction is continuously removed. The xompound formed is generally known as
a) an amine
b) an imine
c) an enamine
d) a Schiffs base

2. Which one of the following is the strongest base in aqueous solution?
a) Trimethylamine
b) Aniline
c) Dimethylamine
d) Methylamine

19. Polymers and Biomolecules - Quiz

1. Synthesis of each molecule of glucose in photosynthesis involves
a) 18 molecules of ATP
b) 10 molecules of ATP
c) 8 molecules of ATP
d) 6 molecules of ATP

2. Which of the following is a polyamide?
a) Bakelite
b) Terylene
c) Nylon-6,6
d) Teflon

20. Analytical Chemistry and Chemistry in Everyday Life - Quiz

1. If Fe³⁺ and Cr³⁺ both in group III of qualitative analysis, then distinction ,can be made by
a) addition of NH₄OH in the presence of NH₄Cl when only Fe(OH)₃ is prexipitated
b) addition of NH₄OH in presence of NH₄ when Ca(OH)₃ and Fe(OH)₃ both are precipitated and on adding Br₂ walter and NaOH , Cr(OH)₃ day dissolves
c) precipitate of Ce(OH)₃ and Fe(OH)₃ as obtained in (b) are treated with conc. HCl when only Fe(OH)₃ dissolves
d) both (b) and (c)

2. 2.9 mg of an organic compound containing nitrogen was digested according to Kjeldahls method and the evolved ammonia was absorbed in 20 mL of 0.1MHCl solution. The excess of the acid required 15Ml of 0.1 M NaOH solution for complete neutralization . The percentage of nitrogen in the compound is
a) 59
b) 47.4
c) 23.7
d) 29.5

Color

Chemistry [Engineering Entrance]

Class/Course - Engineering Entrance

Subject - Chemistry

Total Number of Question/s - 3121