CHEMISTRY  

Multiple choice questions

1.       Volume of 75% H2SO4 by weight (density=1.8 g/ml) required to prepare 1L of 0.5 M solution is

       (a) 36 ml                                                               (b)3.6 ml

       (c) 39 ml                                                               (d) 33 ml

 

2.       A certain buffer solution contains equal concentrations of X- and HX. If Kb for X- is !0-10,calculate pH of the buffer.

(a) 4                                                                              (b) 10

(c) 7                                                                              (d) 14

 

3.       Reagents required for conversion of benzene to hexachlorobenzene are

(a) excess Cl2 , AlCl3                                                    (b) sunlight , excess Cl2

(c) excess Cl2, ZnCl2                                                     (d) sunlight, CaCl2

 

4. The compressibility factor for a real gas at high pressure is 

       (a) 1+RT/pb                                                                 (b) 1

       (c) 1+ pb/RT                                                                (d) 1- pb/RT     

 

5.   Two electrolytic cells containing CuSO4 and AgNO3 are connected in series. Current of 2 A was 

      passed till 10.8 g of Ag got deposited. (At.wt. of Cu = 63,Ag = 108). The amount of Cu deposited in

      the same time will be

(a) 6.3 g                                                                  (b) 1.575 g

(c) 10.8 g                                                                 (d) 3.15 g

 

6.  In a Lechlanche cell which of the following takes place:

(a)    Reduction of Zn2+ to Zn           (b) Reduction of Mn4+ to Mn3+

(c)  Reduction of Mn4+ to Mn2+      (d) Oxidation of Mn3+ to Mn4+

 

7. Standard heat of formation of CH4 , CO2 and H2O(g) are -76.2 , -394.8 and -241.6 kJ/mol

    respectively. The amount of heat evolved on burning 1 m3 of CH4 measured  at STP is

       (a) 801 kJ                                                  (b) 36 kJ

       (c) 36000 kJ                                              (d) 954 kJ      

 

8. Which of the following is NOT true about glucose:

       (a) Reduces Fehling’s solution            (b) Gives Schiff’s test 

       (c) Has  aldehyde group                       (d) Reduces Tollen’s reagent

 

9. The order of intermolecular forces in the following polymers is

       (a) Nylon 6,6 < PVC < Polyethylene          (b) Nylon 6,6 < Polyethylene < PVC

       (c)  PVC < Polyethylene < Nylon 6,6         (d)  Polyethylene < PVC < Nylon 6,6

 

 

10. The rate of a reaction doubles when temperature changes from 27oC to 37oC. The activation 

       energy is

       (a) 53.6 kJ mol-1                                (b) 57.6 x 10 J mol-1

       (c) 53600 kJ mol-1                             (d) 123.4 kJ mol-1     

 

11. Hall-Heroult process is used for the extraction of   

       (a) Ni                                                           (b) Al

       (c) Fe                                                           (d) Cu      

 

12. The equilibrium mixture for

                    2 SO2(g) + O2 (g) à 2SO3(g)

       present in 1 litre vessel at 600oC contains 0.50, 0.12 and 5.0 mole of SO2, O2 and SO3  

       respectively.The Kp for the reaction is

         (a) 22000 atm-1                                            (b) 833 atm -1

         (c) 11.6 atm -1                                                                           (d) 0.114 atm-1

 

13. As per IUPAC nomenclature ,the complex [Co(NH3)2(H2O)4]Cl3

       (a) Tetraaquadiaminecobalt(III)chloride                (b) Tetraaquadiamminecobalt(III)chloride     

       (c) Diaminetetraaquacobalt(III)chloride                (d) Diamminetetraaquacobalt(III)chloride        

 

14. The solubility product (Ksp) of CuS , Ag2S and HgS are 10-31,10-44 and 10-54 respectively. The order

      of their solubility in water is

       (a) CuS<Ag2S<HgS                                     (b) Ag2S <HgS<CuS

       (c) HgS< CuS<Ag2S                                     (d) CuS< HgS <Ag2S

 

15. Which of these salts can be converted into alkyne by Kolbe’s method?

       (a) Sodium succinate                                     (b) Sodium maleate

       (c) Sodium formate                                        (d) Sodium acetate

                          

Numerical answer questions

 16. If the plot of Rate vs Concentration  of reactants is a line parallel to x-axis, the order of the 

      reaction is    0

     

 17. Vant Hoff’s factor for Na2SO4 in very dilute solution is   3

      

 18. The covalency of Nitrogen in N2O5 is     4

 

 19. A 37% (w/w) HCl stock solution has density of 1.18 g/ml. The molecular weight of HCl is 36.5

  g/mol. The volume of stock solution required to prepare 100 ml solution of 6M HCl is      50

      

 20. The total number of lone pair of electrons in melamine is  6