Problem 122
End point in acid base titration is the point where (1) the base is added to the acid (2) the base is exactly neutralized with acid (3) the acid is found in slight excess (4) none
Problem 123
The \(\mathrm{p} K_{\mathrm{a}}\) values of \(\mathrm{A}, \mathrm{B}, \mathrm{C}\) and \(\mathrm{D}\) are \(1.5,4.0,5.5\) and \(9.4\), respectively for a titration at the end point range if neutralization is in between \(6.5\) and \(10.5\). The best suitable indicator is (1) \(\mathrm{A}\) (2) \(B\) (3) \(\mathrm{C}\) (4) D
Problem 124
Which onc of the following is not a postulate of Ostwald's theory of indicators? (1) The colour of an indicator in solution is duc to the ions furnished by it (2) The colour of an indicator is duc to the ions furnished by acidic substancc (3) \Lambdall indicators are weak acids or bases (4) \Lambdacidic indicators show decp colour in acidic solutions and vice versa
Problem 127
The solubility of \(\Lambda \mathrm{gCl}\) in water at \(10^{\circ} \mathrm{C}\) is \(6.2 \times\) \(10^{-6} \mathrm{~mol} /\) litre. The \(K_{\mathrm{p}}\) of \(\Lambda \mathrm{gCl}\) is (1) \(\left[6.2 \times 10^{6}\right]^{2}\) (2) \(\left[6.2 \times 10^{-6}\right]^{2}\) (3) \(6.2 \times\left(10^{-6}\right)^{2}\) (4) \((6.2)^{2} \times 10^{-6}\)
Problem 128
\(K_{\mathrm{sp}}\) of \(\mathrm{AgCl}\) at \(18^{\circ} \mathrm{C}\) is \(1.8 \times 10^{10}\). If \(\mathrm{Ag}\) of solution is \(4 \times 10^{3}\) mol/litre, the Cl that must exceed before \(\mathrm{AgCl}\) is precipitated would be (1) \(4.5 \times 10^{-8} \mathrm{~mol} /\) litre (2) \(7.2 \times 10^{-13} \mathrm{~mol} /\) litrc (3) \(4.0 \times 10^{-3} \mathrm{~mol} /\) litre (4) \(4.5 \times 10^{-7} \mathrm{~mol} /\) itre
Problem 134
When equal volumes of the following solutions are mixed, precipitation of \(\mathrm{AgCl}\left(K_{\mathrm{pp}}=1.8 \times 10^{10}\right)\) will occur only with (1) \(10^{-4} \mathrm{M}\left(\mathrm{Ag}^{-}\right)\) and \(10^{-4} \mathrm{M}\left(\mathrm{Cl}^{-}\right)\) (2) \(10^{-5} \mathrm{M}\left(\Lambda \mathrm{g}^{-}\right)\) and \(10^{-5} \mathrm{M}\left(\mathrm{Cl}^{-}\right)\) (3) \(10^{-6} \mathrm{M}\left(\Lambda \mathrm{g}^{-}\right)\) and \(10^{-6} \mathrm{M}\left(\mathrm{Cl}^{-}\right)\) (4) \(10^{-10} \mathrm{M}\left(\Lambda \mathrm{g}^{-}\right)\) and \(10^{-10} \mathrm{M}\left(\mathrm{Cl}^{-}\right)\)
Problem 137
To \(100 \mathrm{~mL}\) of \(0.1 \mathrm{M} \mathrm{AgNO}_{3}\) solution, solid \(\mathrm{K}_{2} \mathrm{SO}_{4}\) is added. The concentration of \(\mathrm{K}_{2} \mathrm{SO}_{4}\) that shows the precipitation is \(\left(K_{s p}\right.\) for \(\left.\mathrm{A}_{\mathrm{g}_{2}} \mathrm{SO}_{4}=6.4 \times 10^{-5} \mathrm{M}\right)\) (1) \(0.1 \mathrm{M}\) (2) \(6.4 \times 10^{-3} \mathrm{M}\) (3) \(6.4 \times 10^{-7} \mathrm{M}\) (4) \(6.4 \times 10^{-5} \mathrm{M}\)
Problem 143
Let the solubilities of \(\mathrm{AgCl}\) in \(\mathrm{H}_{2} \mathrm{O}, 0.01 \mathrm{M} \mathrm{CaCl}_{2}\); \(0.01 \mathrm{M} \mathrm{NaCl}\) and \(0.05 \mathrm{M} \mathrm{AgNO}_{3}\) be \(\mathrm{S}_{1}, \mathrm{~S}_{2}, \mathrm{~S}_{3}\) and \(\mathrm{S}_{4}\) respectively. What is the correct relationship between these quantities? (1) \(S_{1}>S_{2}>S_{3}>S_{4}\) (2) \(S_{1}>S_{2}=S_{3}>S_{4}\) (3) \(S_{1}>S_{3}>S_{2}>S_{4}\) (4) \(S_{4}>S_{2}>S_{3}>S_{1}\)
Problem 145
\(\Lambda\) saturated solution of \(\mathrm{II}_{2} \mathrm{~S}\) in \(0.1 \mathrm{M} \mathrm{IICl}\) at \(25^{\circ} \mathrm{C}\) contains a \(\mathrm{S}^{2-}\) ion concentration of \(10^{-23} \mathrm{~mol} \mathrm{~L}^{-1}\). The solubility products of some sulphidcs are: \(\mathrm{CuS}=10^{-44}\), \(\mathrm{FeS}=10^{-14} ; \mathrm{MnS}=10^{-15}\) and \(\mathrm{CdS}=10^{-25} .\) If \(0.01 \mathrm{M}\) solutions of these salts in \(1 \mathrm{M}\) IICl are saturated with \(\mathrm{H}_{2} \mathrm{~S}\), which of these will be precipitated? (1) All (2) All except MnS (3) All except MnS and FeS (4) Only CuS
Problem 147
When \(\mathrm{NaCl}\) is added to the reaction mixture of an oil and caustic soda, the soap is thrown out because (1) \(\mathrm{NaCl}\) is an ionic compound (2) Soap is insoluble in the presence of chloride ions (3) The solubility product of \(\mathrm{NaCl}\) decreases in the presence of soap (4) The solubility product of the soap is excceded duc to the increased concentration of \(\mathrm{Na}^{-}\) ions
