Which of the following will decrease the pH of  a 50 mL solu

Previous Year Papers

Download Solved Question Papers Free for Offline Practice and view Solutions Online.

Test Series

Take Zigya Full and Sectional Test Series. Time it out for real assessment and get your results instantly.

Test Yourself

Practice and master your preparation for a specific topic or chapter. Check you scores at the end of the test.
Advertisement

 Multiple Choice QuestionsMultiple Choice Questions

681.

Which ofthese is least likely to act as a Lewis base?

  • CO

  • F-

  • BF3

  • PF3


682.

An electric current is passed through an aqueous solution of a mixture of alanine (isoelectric point 6.0), glutamic acid (3.2) and arginine (10.7) buffered at pH 6. What is the fate of the three acids?

  • Glutamic acid migrates to anode at pH 6. Arginine is present as a cation and migrates to the cathode. Alanine in a dipolar ion remains uniformly distributed in solution

  • Glutamic acid migrates to cathode and others remain uniformly distributed in solution

  • All three remain uniformly distributed in solution

  • All three move to cathode


683.

If the molecular wt. of Na2S2O3 and I2 are M1 and M2 respectively then what will be the equivalent weight of Na2S2O3 and I2 in the following reaction?

2S2O32- + I2  S4O62- + 2I-

  • M1 , M2

  • M1 , M2/2

  • 2M1 , M2

  • M1 , 2M2


684.

The solubility of Ca3(PO4)2 in water is y mol/L. Its solubility product is:

  • 6y4

  • 36y4

  • 64y5

  • 108y5


Advertisement
685.

The equilibrium constant (K) of a reaction may be written as

  • K = e-G/RT

  • K =e-G°/RT

  • K = e-H/RT

  • K = e-H°/RT


686.

For the reaction  SO2 + 12O2  SO3 , if we write Kp = Kc(RT)x, then x become

  • -1

  • -12

  • 12

  • 1


Advertisement

687.

Which of the following will decrease the pH of  a 50 mL solution of 0.01 M HCl?

  • Addition of 5 mL of 1 M HCl

  • Addition of 50 mL of 0.01 M HCl

  • Addition of 50 mL of 0.002 M HCl

  • Addition of Mg


B.

Addition of 50 mL of 0.01 M HCl

Millimoles of 50 mL of 0.01 M HCl
             = 50 x 0.01 M = 0.5
pH of the solution =-log (0.5) = 0.3010

(a) On adding 5 mL of 1 M HCl,
           Concentration of the resultant solution

         =50 × 0.01+ 5 ×150+5=0.1

     :. pH of the solution = -log (0.1) = 1

(b) On adding 50 mL or 0.01 M HCl,
       Concentration of the resultant solution

         =50 x 0.01 + 50 x 0.0150 + 50= 0.01

  :. pH of the solution = -log (0.01) = 2

(c) On adding 50 mL of 0.002 M HCl,
       concentration of the resultant solution

       =50 ×0.01+ 50 x 0.00250 +50= 6×10-3

:. pH of the solution = -log (6 x 10-3)= 2.22

(d) On adding Mg,

    Mg +2HCl  MgCl2 + 2H+  Since, pH  1[H+]:. In this case pH decreases.


Advertisement
688.

Under which of the following conditions is the relation H =E + PV valid for a closed system ?

  • Constant pressure

  • Constant temperature

  • Constant temperature and pressure

  • Constant temperature, pressure and composition


Advertisement
689.

For a reversible chemical reaction where the forward process is exothermic, which of the following statements is correct ?

  • The backward reaction has higher activation energy than the forward reaction.

  • The backward and the forward processes have the same activation energy.

  • The backward reaction has lower activation energy

  • No activation energy is required at all since energy is liberated in the process.


690.

0.1M HCl and 0.1M H2SO4 each of volume 2 mL are mixed and the volume is made upto 6 mL by adding 2 mL of 0.01N NaCl solution. The pH of the resulting mixture is

  • 1.17

  • 1.0

  • 0.3

  • log 2 - log 3


Advertisement