JEE MAIN - Chemistry (2014 (Offline))

• 1

  Resistance of 0.2 M solution of an electrolyte is 50 $$\Omega$$. The specific conductance of the solution is 1.4 S m^-1. The resistance of 0.5 M solution of the same electrolyte is 280 $$\Omega$$. The molar conductivity of 0.5 M solution of the electrolyte in S m² mol^-1 is :

  回答

  (C)

  5 × 10^-4
• 2

  Consider separate solutions of 0.500 M C₂H₅OH(aq), 0.100 M Mg₃(PO₄)₂(aq), 0.250 M KBr(aq) and 0.125 M Na₃PO₄(aq) at 25^oC. Which statement is true about these solutions, assuming all salts to be strong electrolytes?

  回答

  (C)

  They all have the same osmotic pressure
• 3

  For the estimation of nitrogen, 1.4 g of organic compound was digested by Kjeldahl method and the evolved ammonia was absorbed in 60 mL of M/10 sulphuric acid. The unreacted acid required 20 ml of M/10 sodium hydroxide for complete neutralization. The percentage of nitrogen in the compound is:

  回答

  (D)

  10%
• 4

  In which of the following reactions H₂O₂ acts as a reducing agent?
  1. H₂O₂ + 2H⁺ + 2e^- $$\to$$ 2H₂O
  2. H₂O₂ - 2e^- $$\to$$ O₂ + 2H⁺
  3. H₂O₂ + 2e^- $$\to$$ 2OH^-
  4. H₂O₂ + 2OH^- - 2e^- $$\to$$ O₂ + 2H₂O

  回答

  (D)

  2, 4
• 5

  For the reaction SO₂ (g) + $${1 \over 2} O_2(g) \leftrightharpoons$$ SO₃(g).
  if K_P = K_C(RT)^x where the symbols have usual meaning then the value of x is: (assuming ideality)

  回答

  (B)

  -1/2
• 6

  For complete combustion of ethanol, C₂H₅OH(l) + 3O₂(g) $$\to$$ 2CO₂(g) + 3H₂O(l) the amount of heat produced as measured in bomb calorimeter, is 1364.47 kJ mol^–1 at 25^oC. Assuming ideality the Enthalpy of combustion, $$\Delta _CH$$, for the reaction will be : (R = 8.314 kJ mol^–1)

  回答

  (C)

  – 1366.95 kJ mol^–1
• 7

  Given below are the half-cell reactions:
  
  Mn²⁺ + 2e^- $$\to$$ Mn; E^o = -1.18 V
  
  2(Mn³⁺ + e^- $$\to$$ Mn²⁺); E^o = +1.51 V
  
  The E^o for 3Mn²⁺ $$\to$$ Mn + 2Mn³⁺ will be :

  回答

  (C)

  – 2.69 V; the reaction will not occur
• 8

  The ratio of masses of oxygen and nitrogen in a particular gaseous mixture is 1 : 4. The ratio of number of their molecule is:

  回答

  (D)

  7 : 32
• 9

  The major organic compound formed by the reaction of 1, 1, 1– trichloroethane with silver powder is:

  回答

  (A)

  2- Butyne
• 10

  Sodium phenoxide when heated with $$C{O_2}$$ under pressure at $${125^ \circ }C$$ yields a product which on acetylation products $$C.$$
  
  
  
  The major product $$C$$ would be

  回答

  (A)

  
• 11

  Which one of the following bases is not present in DNA?

  回答

  (C)

  Quinoline
• 12

  Considering the basic strength of amines in aqueous solution, which one has the smallest pK_b value?

  回答

  (C)

  (CH₃)₂NH
• 13

  On heating an aliphatic primary amine with chloroform and ethanolic potassium hydroxide, the organic compound formed is:

  回答

  (B)

  an alkyl isocyanide
• 14

  The most suitable reagent for the conversion of R - CH₂ - OH $$\to$$ R - CHO is:

  回答

  (B)

  PCC (Pyridinium Chlorochromate)
• 15

  In the reaction,
  
  the product C is:

  回答

  (A)

  Ethylene
• 16

  In S_N2 reactions, the correct order of reactivity for the following compounds:
  CH₃Cl, CH₃CH ₂Cl, (CH₃)₂CHCl and (CH₃)₃CCl is:

  回答

  (D)

  CH3Cl > CH₃CH₂Cl > (CH₃)₂CHCl > (CH₃)₃CCl
• 17

  The equation which is balanced and represents the correct product(s) is :

  回答

  (D)

  [CoCl(NH₃)₅]⁺ + 5H⁺ $$\to$$ Co²⁺ + $$5NH_4^+$$ + Cl^-
• 18

  The octahedral complex of a metal ion M³⁺ with four monodentate ligands L₁, L₂, L₃ and L₄ absorb wavelengths in the region of red, green, yellow and blue, respectively. The increasing order of ligand strength of the four ligands is :

  回答

  (D)

  L₁ < L₃ < L₂ < L₄
• 19

  Which series of reactions correctly represents chemical relations related to iron and its compound?

  回答

  (D)

  Fe $$\buildrel {{O_2},\,heat} \over \longrightarrow $$ Fe₃O₄ $$\buildrel {CO,\,{{600}^o}C} \over \longrightarrow $$ FeO $$\buildrel {CO,\,{{700}^o}C} \over \longrightarrow $$ Fe
• 20

  The correct statement for the molecule, CsI₃ is :

  回答

  (D)

  it contains Cs⁺ and $$I_3^-$$ ions
• 21

  Which one of the following properties is not shown by NO?

  回答

  (C)

  It is diamagnetic in gaseous state
• 22

  For the non – stoichiometre reaction 2A + B $$\to$$ C + D, the following kinetic data were obtained in three separate experiments, all at 298 K.

  Initial Concentration (A)	Initial Concentration (B)	Initial rate of formation of C (mol L-1 s-1)
  0.1 M	0.1 M	1.2 x 10-3
  0.1 M	0.2 M	1.2 x 10-3
  0.2 M	0.1 M	2.4 x 10-3

  The rate law for the formation of C is:

  回答

  (B)

  $${{dc} \over {dt}} = k[A]$$
• 23

  The equivalent conductance of NaCl at concentration C and at infinite dilution are $${\lambda _C}$$ and $${\lambda _\infty }$$, respectively. The correct relationship between $${\lambda _C}$$ and $${\lambda _\infty }$$ is given as: (where the constant B is positive)

  回答

  (C)

  $${\lambda _C} = {\lambda _\infty } - (B)\sqrt C$$
• 24

  The correct set of four quantum numbers for the valence elections of rubidium atom (Z= 37) is:

  回答

  (C)

  5, 0, 0, + 1/2