## Class/Course - Engineering Entrance

### Subject - Chemistry

#### Total Number of Question/s - 3121

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• 1. Some Basic Concepts of Chemistry - Quiz

1. Number of atoms in 560g of Fe
(atomic mass = 56 g mol-1) is
a) twice that of 70 GN
b) half that of 20 g H
c) both (a) and (b)
d) none of these

2. If we consider that 1/6, in place of 1/12, mass of carbon atom is taken to be the relative atomic mass unit, the mass of one mole of a substance will
a) be a function of the molecular mass of the substance
b) remain unchanged
c) increase two fold
d) decrease twice

• 2. States of Matter - Quiz

1. As the temperature is raised from 200C to 400 , the average kinetic energy of neon atoms changs by a factor of which of the following?
a) 1/2
b) $\sqrt{313/293}$
c) 313/293
d) 2

2. If Z is a compressibility factor, van der Waals' equation at low pressure can be written as
a) Z = $1 + \frac{Rt}{pb}$
b) Z = $1 - \frac{Rt}{VRT}$
c) Z = $1 - \frac{pb}{RT}$
d) Z = $1 + \frac{Pb}{RT}$

• 3. Atomic Structure - Quiz

1. 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

2. The frequency of light emitted for the transition n = 4 to n=2 of He+ is equal to the transition in H atoms corresponding to which of the following?
a) n=3 to n=1
b) n=2 to n=1
c) n=3 to n=2
d) n=4 to n=3

• 4. Chemical Bonding - Quiz

1. Which of the following hydrogen bond is the strongest?
a) O-H....N
b) F-H....F
c) O-H....O
d) O-H....F

2. Among the following the maximum covalent character is shown by the compound
a) FeCl2
b) SnCl2
c) AlCl3
d) MgCl2

• 5. Thermodynamics - Quiz

1. The entropy change involved in the isothermal reversible expansion of 2 moles of an ideal gas from a volume of 10 dm3 to a volume of 100 dm3 at 270 C is
a) 38.3 J mol-1 K-1
b) 35.8 K mol-1 K-1
c) 32.3 J mol-1 K-1
d) 42.3 J mol-1 K-1

2. Heat required to raise the temperature of 1 mole of a substance by 10 is called
a) specific heat
b) molar heat capacity
c) water equivalent
d) specific gravity

• 6. Solutions - Quiz

1. A 5.25% solution of a substance is isotonic with a 1.5 % solution of urea (molar mass = 60 g mol-1) in the same solvent. If the densities of both the solutions are assumed to be equal to 1.0 g cm-3 , molar mass of the substance will be
a) 90.0 g mol-1
b) 115.0 g mol-1
c) 105.0 g mol-1
d) 210. 0 g mol-1

2. Consider the separate solution of 0.500 M C2H5 (aq), 0.100 M Mg3(PO4)2 (aq), 0.250 M KBr (aq) and 0.125 M Na3PO4 (aq) at 250C. What statement is true about these solutions, assuming all salts to be strong electrolytes.
a) They all have same osmotic pressure
b) 0.100 M Mg3(PO4)2 (aq) has the highest osmotic pressure
c) 0.125 M Na3PO4(aq) has the highest osmotic pressure
d) 0.5000 M C2H5OH (aq) has the highest osmotic pressure

• 7. Equilibrium - Quiz

1. For the following three reactions, I, II and III, equilibrium constants are given
I. CO(g) + H2O (g) $\rightleftharpoons$ CO2(g) + H2 (g); K1
II. CH4 (g) + H2O (g) $\rightleftharpoons$ CO(g) + 3H2(g); K1
III. CH4(g) + 2H2O (g) $\rightleftharpoons$ CO2 (g) + 4H2 (g); K3
Which of the following relations is correct?
a) $K_{1}\sqrt{K_{2}}$ = $K_{3}$
b) K2K3 = K1
c) K3=K1K2
d) $K_{3}K_{2}^{3}$ = $K_{1}^{2}$

2. For the reaction
SO2 (g) + $\frac{1}{2}O_{2}\left (g \right ) \rightleftharpoons$ SO3(g),
If Kp = KC (RT)x where the symbols have usual meanings the, the value of x is (assuming ideality).
a) -1
b) $-\frac{1}{2}$
c) $\frac{1}{2}$
d) 1

• 8. Redox Reactions and Electrochemistry - Quiz

1. Given , $E_{Fe^{3+}/Fe}^{0}$ = -0.036V,
$E_{Fe^{2+}/Fe}^{0}$ = -0.439V,
the value of standard electrode potential for the charge,
Fe3+(aq) + e- → Fe2+ (aq) will be
a) -0.072 V
b) 0.385 V
c) 0.770 V
d) -0.270 V

2. The Gibbs energy for the decomposition of Al2O3 at 5000C is as follows
$\frac{2}{3}Al_{2}O_{3} \rightarrow \frac{4}{3}Al + O_{2}$
ΔrG = + 966 kJ mol-1
The potential difference needed for electrolyte reduction of Al2O3 at 5000C is at least
a) 4.5 V
b) 3.0 V
c) 2.5 V
d) 5.0 V

• 9. Chemical Kinetics and Surface Chemistry - Quiz

1. For a first order reaction , (A) → products the concentration of A changes from 0.1 M to 0.025 M in 40 min. The rate of reaction when the concentration of A is 0.01 M is
a) 1.73 x 10-5 M/min
b) 3.47 x 10-4 M/min
c) 3.47 x 10-5 M/min
d) 1.73 x 10-4 M/min

2. Rate of a reaction can be expressed by Arrhenius equation as k = Ae-E/RT
In this equation, E represents
a) the energy above which all the colliding molecules will react
b) the energy below which colloiding molecules will not react
c) the total energy of the reacting molecules at a temperature T
d) the fraction of molecules with energy greater than the activation energy of the reaction

• 10. Periodicity of Elements - Quiz

1. In which of the following arrangements the order is not according to the property indicated against it?
a) Li < Na < K < Rb Increasing metallic radius
b) I < Br < F < Cl Increasing electron gain enthalpy ( with negative sign)
c) B < C < N < O Increasing first ionisation enthalpy
d) Al3+ < Mg2+ < Na+ < F- Increasing ionic size

2. The atomic numbers of vanadium (V), chromium (Cr), manganese (Mn) and iron (Fe) are, respectively 23, 24, 25 and 26, Which one of these may be expected to have the highest second ionisation enthalpy?
a) V
b) Cr
c) Mn
d) Fe

• 11. Principles and Processes of Metallurgy - Quiz

1. During the process of electrolytic refining of copper, some metals present as impurity settle as anode mud. These are
a) Fe and Ni
b) Ag and Au
c) Pb and Zn
d) Se and Ag

2. Which one of the following ores is best concentrated by froth-floatation method?
a) magnetite
b) Cassiterite
c) Galena
d) Malachite

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

1. Which of the following exists as covalent crystals in the solid state?
a) Iodine
b) Silicon
c) Sulphur
d) Phosphorous

2. Aluminium chloride exists as dimer, Al2Cl6 in solid state as well as in solution of non-polar solvents such as benzene . When dissolved in water, it gives
a) Al3+ + 3Cl-
b) [A][H2O)6]3+ + 3Cl-
c) [Al](OH)6]3- + 3HCl
d) Al2O3 + 6HCl

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

1. Iron exhibits +2 and +3 oxidation sates . Which of the following statements about iron is incorrect?
a) Ferrous oxide is more basic in nature than the ferric oxide
b) Ferrous compounds are relatively more ionic than the corresponding ferric compounds
c) Ferrous compounds are less volatile than the corresponding ferric compounds
d) Ferrous compounds are more easily hydrolysed than the corresponding ferric compounds

2. Which of the following facts about the complex [Cr(NH3)6]Cl3 is wrong?
a) The complex involves d2sp3 hybridization and is octahedral in shape
b) The comples is paramagnetic
c) The complex is an outer orbital complex
d) The complex gives white precipitate with silver nitrate solution

• 14. Environmental Chemistry - Quiz

1. Identify the incorrect statement from the following
a) Oxides of nitrogen in the atmosphere can cause the depletion of ozone layer
b) Ozone absorbs the intense ultraviolet radiations of the sun
c) Depletion of ozone layer is because of its chemical reactions with chlorofluoro alkenes

2. When rain is accompanied by a thunderstorm, the collected rain water will have a pH value
a) slightly lower than that of rain water without thunderstorm
b) slightly higher than that when the thunderstorm is not there
c) unifluenced by occurrence of thunderstorm
d) which depends on the amount of dust in air

• 15. General Organic Chemistry - Quiz

1. The order of stability of the following carbocations

a) III > II > I
b) II > III > I
c) I > II > III
d) III > I > II

2. Underlined carbon is sp3 hybridised in
a) $CH_{3}\underline{C}H = CH_{2}$
b) $CH_{3}\underline{C}H_{2}NH_{2}$
c) $CH_{3}\underline{C}ONH_{2}$
d) $CH_{3}CH_{2}\underline{C}H$

• 16. Hydrocarbons and their Halogen Derivatives - Quiz

1. Presence of a nitro group in a benzene ring
a) activates the ring towards electrophilic substitution
b) renders the ring basic
c) deactivates the ring towards nucleophilic substitution
d) deactivates the ring towards electrophilic substitution

2. Ozonolysis of an organic compound gives formaldehyde as one of the products. This confirms the presence of
a) two ethylenic double bonds
b) a vinyl group
c) an iso propyl group
d) an acetylenic triple bond

• 17. Organic Compounds Containing Oxygen - Quiz

1. The general formula CnH2nO2 could be for open chain
a) diketones
b) carboxylic acids
c) diols
d) dialdehydes

2. In the following sequence of reactions,
$CH_{3}CH_{2}OH \overset{P+I_{2}}{\rightarrow} A \xrightarrow[ether]{Mg} B \overset{HCHO}{\rightarrow} C \overset{H_{2}O}{\rightarrow}D$
the compound D is
a) butanal
b) n-butyl alcohol
c) n-propyl alcohol
d) propanal

• 18. Organic Compounds Containing Nitrogen - Quiz

1. On heating benzyl amine with chloroform and ethanolic KOH, product obtained by
a) benzyl alcohol
b) benzaldehyde
c) benzonitrile
d) benzyl isocyanide

2. Wich of the following is the strongest base?
a)
b)
c)
d)

• 19. Polymers and Biomolecules - Quiz

1. Biuret test is not given by
a) carbohyd ates
b) polypeptides
c) urea
d) proteins

2. The reason for double helical structure of DNA is operation of
a) van der Waals forces
b) dipole-dipole interaction
c) hydrogen bonding
d) electrostatic attractions

• 20. Analytical Chemistry and Chemistry in Everyday Life - Quiz

1. For the estimation of nitrogen , 1.4 g of an organic compound was digested by kjeldahls method and the evolved ammonia was absorbed in 6 mL of $\frac{M}{10}$ sulphuric acid .The unreacted acid required 20 mL of $\frac{M}{10}$ sodium hydroxide for the complete neutralization .The percentage of nitrogen in the compound is
a) 6%
b) 10%
c) 3%
d) 5%

2. 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)