JEE MAIN - Chemistry (2018 (Offline))

  • 1
    The increasing order of basicity of the following compounds is : JEE Main 2018 (Offline) Chemistry - Compounds Containing Nitrogen Question 204 English
    Απάντηση
    (D)
    (b) < (a) < (d) < (c)
  • 2
    An alkali is titrated against an acid with methyl orange as indicator, which of the following is a correct combination?
    Απάντηση
    (C)
    Base Acid End point
    Weak Strong Yellow to pinkish red
  • 3
    The predominant form of histamine present in human blood is (pKa, Histidine = 6.0)
    Απάντηση
    (A)
    JEE Main 2018 (Offline) Chemistry - Biomolecules Question 151 English Option 1
  • 4
    Glucose on prolonged heating with HI gives
    Απάντηση
    (B)
    n-Hexane
  • 5
    The major product formed in the following reaction is : JEE Main 2018 (Offline) Chemistry - Alcohols, Phenols and Ethers Question 151 English
    Απάντηση
    (A)
    JEE Main 2018 (Offline) Chemistry - Alcohols, Phenols and Ethers Question 151 English Option 1
  • 6
    Phenol reacts with methyl chloroformate in the presence of NaOH to form product A. A reacts with Br2 to form product B. A and B are respectively :
    Απάντηση
    (D)
    JEE Main 2018 (Offline) Chemistry - Alcohols, Phenols and Ethers Question 152 English Option 4
  • 7
    Phenol on treatment with CO2 in the presence of NaOH followed by acidification produces compound X as the major product. X on treatment with (CH3CO)2O in the presence of catalytic amount of H2SO4 produces:
    Απάντηση
    (B)
    JEE Main 2018 (Offline) Chemistry - Alcohols, Phenols and Ethers Question 153 English Option 2
  • 8
    The trans-alkenes are formed by the reduction of alkynes with
    Απάντηση
    (D)
    Na/liq. NH3
  • 9
    The major product of the following reaction is: JEE Main 2018 (Offline) Chemistry - Haloalkanes and Haloarenes Question 147 English
    Απάντηση
    (C)
    JEE Main 2018 (Offline) Chemistry - Haloalkanes and Haloarenes Question 147 English Option 3
  • 10
    Which of the following compounds will be suitable for Kjeldahl’s method for nitrogen estimation?
    Απάντηση
    (C)
    JEE Main 2018 (Offline) Chemistry - Practical Organic Chemistry Question 79 English Option 3
  • 11
    The compound that does not produce nitrogen gas by the thermal decomposition is :
    Απάντηση
    (A)
    (NH4)2SO4
  • 12
    The oxidation states of Cr in [Cr(H2O)6]Cl3, [Cr(C6H6)2] and K2[Cr(CN)2(O)2(O2)(NH3)] respectively are :
    Απάντηση
    (D)
    +3, 0 and +6
  • 13
    Consider the following reaction and statements:
    [Co(NH3)4Br2]+ + Br- $$\to$$ [Co(NH3)3Br3] + NH3
    (I) Two isomers are produced if the reactant complex ion is a cis-isomer
    (II) Two isomers are produced if the reactant complex ion is a trans-isomer
    (III) Only one isomer is produced if the reactant complex ion is a trans-isomer
    (IV) Only one isomer is produced if the reactant complex ion is a cis – isomer
    The correct statements are
    Απάντηση
    (C)
    (I) and (III)
  • 14
    Which of the following compounds contain(s) no covalent bond(s)? KCl, PH3, O2, B2H6, H2SO4
    Απάντηση
    (D)
    KCl
  • 15
    How long (approximate) should water be electrolysed by passing through 100 amperes current so that the oxygen released can completely burn 27.66 g of diborane?
    (Atomic weight of B = 10.8 u)
    Απάντηση
    (D)
    3.2 hours
  • 16
    At 518oC the rate of decomposition of a sample of gaseous acetaldehyde initially at a pressure of 363 Torr, was 1.00 Torr s–1 when 5% had reacted and 0.5 Torr s–1 when 33% had reacted. The order of the reaction is
    Απάντηση
    (B)
    2
  • 17
    Which of the following salts is the most basic in aqueous solution?
    Απάντηση
    (C)
    CH3COOK
  • 18
    Which of the following are Lewis acids?
    Απάντηση
    (A)
    BCl3 and AlCl3
  • 19
    An aqueous solution contains 0.10 M H2S and 0.20 M HCl. If the equilibrium constants for the formation of HS from H2S is 1.0 $$\times$$ 10–7 and that of S2- from HS ions is 1.2 $$\times$$ 10–13 then the concentration of S2- ions in aqueous solution is :
    Απάντηση
    (C)
    3 $$\times$$ 10–20
  • 20
    An aqueous solution contains an unknown concentration of Ba2+. When 50 mL of a 1 M solution of Na2SO4 is added, BaSO4 just begins to precipitate. The final volume is 500 mL. The solubility product of BaSO4 is 1 $$\times$$ 10–10. What is the original concentration of Ba2+?
    Απάντηση
    (D)
    1.1 $$\times$$ 10–9 M
  • 21
    For 1 molal aqueous solution of the following compounds, which one will show the highest freezing point?
    Απάντηση
    (A)
    [Co(H2O)3 Cl3].3H2O
  • 22
    Which of the following lines correctly show the temperature dependence of equilibrium constant K, for an exothermic reaction? JEE Main 2018 (Offline) Chemistry - Thermodynamics Question 166 English
    Απάντηση
    (B)
    A and B
  • 23
    The combustion of benzene(l) gives CO2(g) and H2O(l). Given that heat of combustion of benzene at constant volume is –3263.9 kJ mol–1 at 25oC; heat of combustion (in kJ mol–1) of benzene at constant pressure will be :
    (R = 8.314 JK–1 mol–1)
    Απάντηση
    (A)
    –3267.6
  • 24
    Total number of lone pair of electrons in $${\rm I}_3^ - $$ ion is
    Απάντηση
    (B)
    9
  • 25
    According to molecular orbital theory, which of the following will not be a viable molecule?
    Απάντηση
    (D)
    $${\rm H}_2^{2 - }$$
  • 26
    The ratio of mass percent of C and H of an organic compound (CXHYOZ) is 6 : 1. If one molecule of the above compound (CXHYOZ) contains half as much oxygen as required to burn one molecule of compound CXHY completely to CO2 and H2O. The empirical formula of compound CXHYOZ is
    Απάντηση
    (A)
    C2H4O3