Practice Questions

Q60.Which of the following molecules is expected to rotate the plane of plane polarized light? (1) (2) (3) (4)

Q61.Which one of the following conformation of cyclohexane is chiral? (1) Twist boat (2) Rigid (3) Chair (4) Boat

Q62. The IUPAC name of is (1) 1, 1−diethyl −2, 2−dimethylpentane (2) 4, 4−dimethyl −5, 5−diethylpentane (3) 5, 5−diethyl −4, 4−diemthylpentane (4) 3−ethyl −4, 4−dimethylheptane

Q63.The reaction of toluene with Cl2 in presence of FeCl3 gives predominantly (1) benzoyl chloride (2) benzyl chloride (3) o−and p−chlorotoluene (4) m−chlorotoluene

Q64.Presence of a nitro group in a benzene ring (1) activates the ring towards electrophilic (2) renders the ring basic substitution (3) deactivates the ring towards nucleophilic (4) deactivates the ring towards electrophilic substitution substitution

Q65.A mixture of ethyl alcohol and propyl alcohol has a vapour pressure of 290 mm at 300 K . The vapour pressure of propyl alcohol is 200 mm. If the mole fraction of ethyl alcohol is 0.6 , its vapour pressure (in mm) at the same temperature will be (1) 350 (2) 300 (3) 700 (4) 360 JEE Main 2007 JEE Main Previous Year Paper

Q66.The cell, Zn Zn2+(1M)∥Cu2+(1M) Cu (E0cell = 1.10 V) , was allowed to be completely discharged at 298 K. [Zn2+] The relative concentration of Zn2+ to Cu2+ is [ [Cu2+] ] (1) antilog (24.08) (2) 37.3 (3) 1037.3 (4) 9.65 × 104

Q67.The equivalent conductances of two strong electrolytes at infinite dilution in H2O (where ions move freely through a solution) at 25∘C are given below: ∧∘CH3COONa = 91.0 S cm2 /equiv ∧∘HCl = 426.2 S cm2 / equiv What additional information/quantity one needs to calculate ∧∘ of an aqueous solution of acetic acid? (1) ∧∘ of NaCl (2) ∧∘ of CH3COOK (3) The limiting equivalent conductance of (4) ∧∘ of chloroacetic acid (C/CH2COOH) H+ (∧∘H+)

Q68.The energies of activation for forward and reverse reactions for A2 + B2 ⇌2AB are 180 kJ mol−1 and 200 kJ mol−1 respectively. The presence of catalyst lowers the activation energy of both (forward and reverse) reactions by 100 kJ mol−1 . The enthalpy change of the reaction (A2 + B2 ⟶2AB) in the presence of catalyst will be (in kJ mol−1 ) (1) 300 (2) 120 (3) 280 (4) 20

Q69.Consider the reaction, 2A + B → Products When concentration of B alone was doubled, the half-life did not change. When the concentration of A alone was doubled, the rate increased by two times. The unit of rate constant for this reaction is (1) L mol−1 s−1 (2) no unit (3) mol L−1 s−1 (4) s−1

Q70.A radioactive element gets spilled over the floor of a room. Its half-life period is 30 days. If the initial activity is ten times the permissible value, after how many days will it be safe to enter the room? (1) 1000 days (2) 300 days (3) 10 days (4) 100 days

Q71.Identify the incorrect statement among the following (1) Ozone reacts with SO2 to give SO3 (2) Silicon reacts with NaOH(aq) in the presence of air to give Na2SiO3 and H2O (3) Cl2 reacts with excess of NH3 to give N2 and (4) Br2 reacts with hot and strong NaOH solution to HCl give NaBr, NaBrO4 and H2O

Q72.Identify the incorrect statement among the following (1) d− Block elements show irregular and erratic (2) La and Lu have partially filled d orbitals and no chemical properties among themselves other partially filled orbitals (3) The chemistry of various lanthanoids is very (4) 4f and 5f orbitals are equally shielded similar

Q73.The actinoids exhibits more number of oxidation states in general than the lanthanoids. This is because JEE Main 2007 JEE Main Previous Year Paper (1) the 5f orbitals are more buried than the 4f (2) there is a similarity between 4f and 5f orbitals in orbitals their angular part of the wave function (3) the actinoids are more reactive than the (4) the 5f orbitals extend further from the nucleus lanthanoids than the 4f orbitals

Q74.Which of the following nuclear reactions will generate an isotope? (1) neutron particle emission (2) positron emission (3) α-particle emission (4) β-particle emission

Q75.Which one of the following has a square planar geometry? (1) [CoCl4]2− (2) [FeCl4]2− (3) [NiCl4]2− (4) [PtCl4]2−

Q76.Which of the following reactions will yield 2, 2−dibromopropane? (1) CH3 −C ≡CH + 2HBr ⟶ (2) CH3CH ≡CHBr + HBr ⟶ (3) CH ≡CH + 2HBr ⟶ (4) CH3 −CH = CH2 + HBr ⟶

Q77.Which of the following is the correct order of decreasing SN2 reactivity? (1) RCH2X > R3CX > R2CHX (2) RCH2X > R2CHX > R3CX (3) R3CX > R2CHX > RCH2X (4) R2CHX > R3CX > RCH2X (X = a halogen )

Q78. In the following sequence of reactions, the compound ' D ' is (1) butanal (2) n−butyl alcohol (3) n−propyl alcohol (4) propanal

Q79.The compound formed as a result of oxidation of ethyl benzene by KMnO4 is (1) benzophenone (2) acetophenone (3) benzoic acid (4) benzyl alcohol

Q80.In the chemical reaction, CH3CH2NH2 −CHCl3 + 3KOH ⟶(A) + (B) + 3H2O, the compound (A) and (B) are respectively (1) C2H5CN and 3KCl (2) CH3CH2CONH2 and 3KCl (3) C2H5NC and K2CO3 (4) C2H5NC and 3KCl

Q81.Which one of the following is the strongest base in aqueous solution? (1) Trimethylamine (2) Aniline (3) Dimethylamine (4) Methylamine

Q82.The secondary structure of a protein refers to (1) α-helical backbone (2) hydrophobic interactions (3) sequence of α-amino acids (4) fixed configuration of the polypeptide backbone

Q83.If the difference between the roots of the equation x2 + ax + 1 = 0 is less than √5, then the set of possible values of a is JEE Main 2007 JEE Main Previous Year Paper (1) (−3, 3) (2) (−3, ∞) (3) (3, ∞) (4) (−∞, −3)

Q84.If |z + 4| ≤3 , then the maximum value of |z + 1| is (1) 4 (2) 10 (3) 6 (4) 0