Other Chemistry · JEE Main previous year questions

2002 25 questions

1. Q1492002 · 27 Apr 2002 · Shift 1

   With increase of temperature, which of these changes?

   1. A.molality
   2. B.weight fraction of solute
   3. C.molarity
   4. D.mole fraction
   Show answer

   Answer: C

2. Q1502002 · 27 Apr 2002 · Shift 1

   Number of atoms in 558.5 gram Fe (at. wt. of Fe = 55.85 $\mathrm{g}\mathrm{mo}{\mathrm{l}}^{-1}$) is

   1. A.twice that in 60 g carbon
   2. B.$6.023\times 10^{22}$
   3. C.half that in 8 g He
   4. D.$558.5\times 6.023\times 10^{23}$
   Show answer

   Answer: A

3. Q1512002 · 27 Apr 2002 · Shift 1

   In a hydrogen atom, if energy of an electron in ground state is -13.6 eV, then that in the 2${}^{nd}$ excited state is

   1. A.-1.51 eV
   2. B.-3.4 eV
   3. C.-6.04 eV
   4. D.-13.6 eV
   Show answer

   Answer: A

4. Q1542002 · 27 Apr 2002 · Shift 1

   Which of the following are arranged in an increasing order of their bond strengths?

   1. A.${\mathrm{O}}_2^{-}<{\mathrm{O}}_2<{\mathrm{O}}_2^{+}<{\mathrm{O}}_2^{2-}$
   2. B.${\mathrm{O}}_2^{2-}<{\mathrm{O}}_2^{-}<{\mathrm{O}}_2<{\mathrm{O}}_2^{+}$
   3. C.${\mathrm{O}}_2^{-}<{\mathrm{O}}_2^{2-}<{\mathrm{O}}_2<{\mathrm{O}}_2^{+}$
   4. D.${\mathrm{O}}_2^{+}<{\mathrm{O}}_2<{\mathrm{O}}_2^{-}<{\mathrm{O}}_2^{2-}$
   Show answer

   Answer: B

5. Q1582002 · 27 Apr 2002 · Shift 1

   For the reactions $\mathrm{C}+{\mathrm{O}}_2\to \mathrm{C}{\mathrm{O}}_2$; $\Delta H$ = -393 J $2Zn+{\mathrm{O}}_2\to 2ZnO$; $\Delta H$ = -412 J

   1. A.carbon can oxidise Zn
   2. B.oxidation of carbon is not feasible
   3. C.oxidation of Zn is not feasible
   4. D.Zn can oxidise carbon
   Show answer

   Answer: D

6. Q1602002 · 27 Apr 2002 · Shift 1

   1 M NaCl and 1 M HCl are present in an aqueous solution. The solution is

   1. A.not a buffer solution with pH < 7
   2. B.not a buffer solution with pH > 7
   3. C.a buffer solution with pH < 7
   4. D.a buffer solution with pH > 7
   Show answer

   Answer: A

7. Q1632002 · 27 Apr 2002 · Shift 1

   Change in volume of the system does not alter which of the following equilibria?

   1. A.${\mathrm{N}}_2(\mathrm{g})+{\mathrm{O}}_2(\mathrm{g})\leftrightharpoons 2NO(\mathrm{g})$
   2. B.$\mathrm{PC}{\mathrm{l}}_5(\mathrm{g})\leftrightharpoons \mathrm{PC}{\mathrm{l}}_3(\mathrm{g})+\mathrm{C}{\mathrm{l}}_2(\mathrm{g})$
   3. C.${\mathrm{N}}_2(\mathrm{g})+3{\mathrm{H}}_2(\mathrm{g})\leftrightharpoons 2N{\mathrm{H}}_3(\mathrm{g})$
   4. D.$\mathrm{S}{\mathrm{O}}_2\mathrm{C}{\mathrm{l}}_2(\mathrm{g})\leftrightharpoons \mathrm{S}{\mathrm{O}}_2(\mathrm{g})+\mathrm{C}{\mathrm{l}}_2(\mathrm{g})$
   Show answer

   Answer: A

8. Q1702002 · 27 Apr 2002 · Shift 1

   Racemic mixture is formed by mixing two

   1. A.isomeric compounds
   2. B.enantiomers with chiral compounds
   3. C.meso compounds
   4. D.optical isomers
   Show answer

   Answer: B

9. Q1712002 · 27 Apr 2002 · Shift 1

   The reaction : $(\mathrm{C}{\mathrm{H}}_3{)}_3\mathrm{C}-\mathrm{Br}\stackrel{{\mathrm{H}}_2\mathrm{O}}{\to }(\mathrm{C}{\mathrm{H}}_3{)}_3\mathrm{C}-\mathrm{OH}$

   1. A.elimination reaction
   2. B.substitution reaction
   3. C.free radical reaction
   4. D.displacement reaction
   Show answer

   Answer: B

10. Q1752002 · 27 Apr 2002 · Shift 1

    In a mixture of A and B, components show negative deviation when :

    1. A.$\Delta V_{mix}>0,\Delta S_{mix}>0$
    2. B.$\Delta V_{mix}=0,\Delta S_{mix}>0$
    3. C.A - B interaction is weaker than A - A and B - B interaction
    4. D.A - B interaction is stronger than A - A and B - B interaction
    Show answer

    Answer: D

11. Q1772002 · 27 Apr 2002 · Shift 1

    EMF of a cell in terms of reduction potential of its left and right electrodes is :

    1. A.$E=E_{left}-E_{right}$
    2. B.$E=E_{left}+E_{right}$
    3. C.$E=E_{right}-E_{left}$
    4. D.$E=-(E_{right}+E_{left})$
    Show answer

    Answer: C

12. Q1782002 · 27 Apr 2002 · Shift 1

    For the following cell with hydrogen electrodes at two different pressures $p_1$ and $p_2$. What will be the emf for the given cell : $$\underset{p_1}{\mathrm{Pt}({\mathrm{H}}_2)}|\underset{1M}{{\mathrm{H}}^{+}(\mathrm{aq})}|\underset{p_2}{\mathrm{Pt}({\mathrm{H}}_2)}$$

    1. A.$\frac{RT}{F}{\log }_e\frac{P_1}{P_2}$
    2. B.$\frac{RT}{2F}{\log }_e\frac{P_1}{P_2}$
    3. C.$\frac{RT}{F}{\log }_e\frac{P_2}{P_1}$
    4. D.none of these
    Show answer

    Answer: B

13. Q1862002 · 27 Apr 2002 · Shift 1

    The integrated rate equation is $Rt=\log C_0-\log C_t$ . The straight line graph is obtained by plotting

    1. A.time vs $\log C_t$
    2. B.$\frac{1}{time}$ vs $C_t$
    3. C.time vs $C_t$
    4. D.$\frac{1}{time}$ vs $\frac{1}{C_t}$
    Show answer

    Answer: A

14. Q1872002 · 27 Apr 2002 · Shift 1

    $\beta$ - particle is emitted in radioactivity by

    1. A.conversion of proton to neutron
    2. B.from outermost orbit
    3. C.conversion of neutron to proton
    4. D.$\beta$ -particle is not emitted
    Show answer

    Answer: C

15. Q1882002 · 27 Apr 2002 · Shift 1

    Which of the following statements is true?

    1. A.HF is less polar than HBr
    2. B.absolutely pure water does not contain any ions
    3. C.chemical bond formation takes place when forces of attraction overcome the forces of repulsion
    4. D.in covalency transference of electron takes place
    Show answer

    Answer: C

16. Q1942002 · 27 Apr 2002 · Shift 1

    $\mathrm{C}{\mathrm{H}}_3$ - Mg - Br is an organometallic compound due to :

    1. A.Mg - Br bond
    2. B.C - Mg bond
    3. C.C - Br bond
    4. D.C - H bond
    Show answer

    Answer: B

17. Q1952002 · 27 Apr 2002 · Shift 1

    The most stable ion is :

    1. A.$[\mathrm{Fe}(\mathrm{OH}{)}_3{]}^{3-}$
    2. B.$[\mathrm{Fe}(\mathrm{Cl}{)}_6{]}^{3-}$
    3. C.$[\mathrm{Fe}(\mathrm{CN}{)}_6{]}^{3-}$
    4. D.$[\mathrm{Fe}({\mathrm{H}}_2\mathrm{O}{)}_6{]}^{3+}$
    Show answer

    Answer: C

18. Q1962002 · 27 Apr 2002 · Shift 1

    $$\mathrm{C}{\mathrm{H}}_3\mathrm{C}{\mathrm{H}}_2\mathrm{COOH}\underset{\text{red P}}{\overset{\mathrm{C}{\mathrm{l}}_2}{\to }}\mathrm{A}\stackrel{\text{Alc. KOH}}{\to }\mathrm{B}$$ What is B?

    1. A.$\mathrm{C}{\mathrm{H}}_3\mathrm{C}{\mathrm{H}}_2\mathrm{COCl}$
    2. B.$\mathrm{C}{\mathrm{H}}_3\mathrm{C}{\mathrm{H}}_2\mathrm{CHO}$
    3. C.$\mathrm{C}{\mathrm{H}}_2=\mathrm{CHCOOH}$
    4. D.$\mathrm{ClC}{\mathrm{H}}_2\mathrm{C}{\mathrm{H}}_2\mathrm{COOH}$
    Show answer

    Answer: C

19. Q1992002 · 27 Apr 2002 · Shift 1

    How do we differentiate between $\mathrm{F}{\mathrm{e}}^{3+}$ and $\mathrm{C}{\mathrm{r}}^{3+}$ in group III?

    1. A.by taking excess of $\mathrm{N}{\mathrm{H}}_4\mathrm{OH}$ solution
    2. B.by increasing $\mathrm{N}{\mathrm{H}}_4^{+}$ ion concentration
    3. C.by decreasing $\mathrm{O}{\mathrm{H}}^{-}$ ion concentration
    4. D.both (b) and (c)
    Show answer

    Answer: B

20. Q2042002 · 27 Apr 2002 · Shift 1

    On vigorous oxidation by permanaganate solution. $(\mathrm{C}{\mathrm{H}}_3{)}_2\mathrm{C}=\mathrm{CH}-\mathrm{C}{\mathrm{H}}_2-\mathrm{CHO}$ gives

    1. A.$(\mathrm{C}{\mathrm{H}}_3{)}_2\mathrm{CO}$ and $\mathrm{OHC}-\mathrm{C}{\mathrm{H}}_2-\mathrm{CHO}$
    2. B.$(\mathrm{C}{\mathrm{H}}_3{)}_2\mathrm{C}(\mathrm{OH})-\mathrm{CH}(\mathrm{OH})-\mathrm{C}{\mathrm{H}}_2\mathrm{CHO}$
    3. C.$(\mathrm{C}{\mathrm{H}}_3{)}_2\mathrm{CO}$ and $\mathrm{OHC}-\mathrm{C}{\mathrm{H}}_2-\mathrm{COOH}$
    4. D.$(\mathrm{C}{\mathrm{H}}_3{)}_2\mathrm{CO}$ and $\mathrm{C}{\mathrm{H}}_2(\mathrm{COOH}{)}_2$
    Show answer

    Answer: D

21. Q2112002 · 27 Apr 2002 · Shift 1

    Kinetic theory of gases proves

    1. A.only Boyle's law
    2. B.only Charle's law
    3. C.only Avogadro's law
    4. D.All of these
    Show answer

    Answer: D

22. Q2142002 · 27 Apr 2002 · Shift 1

    A metal M readily forms its sulphate $\mathrm{MS}{\mathrm{O}}_4$, which is water-soluble. It forms its oxide MO which becomes inert on heating. It forms an insoluble hydroxide $\mathrm{M}(\mathrm{OH}{)}_2$ which is soluble in NaOH solution. The M is :

    1. A.Mg
    2. B.Ba
    3. C.Ca
    4. D.Be
    Show answer

    Answer: D

23. Q2192002 · 27 Apr 2002 · Shift 1

    Alum helps in purifying water by :

    1. A.forming Si complex with clay particles
    2. B.sulphate part which combines with the dirt and removes it
    3. C.coagulating the mud particles
    4. D.making mud water soluble
    Show answer

    Answer: C

24. Q2242002 · 27 Apr 2002 · Shift 1

    When ${\mathrm{H}}_2\mathrm{S}$ is passed through $\mathrm{H}{\mathrm{g}}_2\mathrm{S}$ we get :

    1. A.HgS
    2. B.$\mathrm{HgS}+\mathrm{H}{\mathrm{g}}_2\mathrm{S}$
    3. C.$\mathrm{H}{\mathrm{g}}_2\mathrm{S}$
    4. D.$\mathrm{H}{\mathrm{g}}_2{\mathrm{S}}_2$
    Show answer

    Answer: B

25. Q2252002 · 27 Apr 2002 · Shift 1
    
    1. A.antiseptic
    2. B.antibiotic
    3. C.analgesic
    4. D.pesticide
    Show answer

    Answer: C