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1.

When 100 mL of 1.0 M  HCl was mixed with 100mL   of 1.0 M NaOH in an insulated beaker at constant pressure, a temperature increase of 5.7° C was measured for the beaker and its contents (Expt. I). Because the enthalpy of neutralisation of a strong acid with a strong base is a constant  (-57.0kJmol-1), this experiment could be used to measure the calorimeter constant.In a second  experiment  (Expt.2), 100mL  of 2.0 M  acetic acid  (Ka = 2.0 x 10-5) was mixed with 100 mL of 1.0 M   NaOH  (under identical conditions  to  Expt. 1)  where a temperature rise of 5.6° C was measured

The pH  of the solution after Expt.2 is 


A) 2.8

B) 4.7

C) 5.0

D) 7.0



2.

When 100 mL of 1.0 M  HCl was mixed with 100mL   of 1.0 M NaOH in an insulated beaker at constant pressure, a temperature increase of 5.7° C was measured for the beaker and its contents (Expt. I). Because the enthalpy of neutralisation of a strong acid with a strong base is a constant  (-57.0kJmol-1), this experiment could be used to measure the calorimeter constant. In a second experiment  (Expt.2), 100mL  of 2.0 M  acetic acid  (Ka = 2.0 x 10-5) was mixed with 100 mL of 1.0 M   NaOH  (under identical conditions to  Expt. 1)  where a temperature rise of 5.6° C was measured.

Enthalpy of disscociation (in KJmol-1) of acetiic acid  obtained from the Expt. 2 is 


A) 1.0

B) 10.0

C) 24.5

D) 51.4



3.

The pair(s)  of ions where both the ions are precipitated upon passing H2S  gas in presence of dilute HCl,  is (are)


A) $Ba^{2+},Zn^{2+}$

B) $Bi^{3+},Fe^{3+}$

C) $Cu^{2+},Pb^{2+}$

D) $Hg^{2+},Bi^{3+}$



4.

The correct statement(s) regarding, $(i)  HClO,(ii) HClO_{2},(iii) HClO_{3}$  and  $HClO_{4}$  is(are)


A) the number of Cl=O bonds in(ii) and (iii) together is two

B) the number of lone pair of electrons on Cl in(ii) and (iii) together in three.

C) the hybridisatin of Cl in(iv) in $sp^{3}$

D) amongest (i) and (iv) , the strongest acid is(i)



5.

When O2  is absorbed on a metallic surface, electron transfer occurs from the metal to O2. The true statement (s)  regarding this adsorption is(are)  


A) $O_{2}$ is physisorbed

B) heat released

C) Occupancy of $^{*}\pi_{2\rho}$ of $O_{2}$ is increased

D) bond length of $O_{2}$ is increased



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