5 questions
A solution is prepared by mixing \( 0.01 \) mol each of \( \mathrm{H_2CO_3} \), \( \mathrm{NaHCO_3} \), \( \mathrm{Na_2CO_3} \), and \( \mathrm{NaOH} \) in \( 100 \ \mathrm{mL} \) of water. pH of the resulting solution is _______.
\([ \text{Given : } pK_{a_1} \text{ and } pK_{a_2} \text{ of } \mathrm{H_2CO_3} \text{ are } 6.37 \text{ and } 10.32, \text{ respectively; } \log 2 = 0.30 ]\)
On decreasing the \( \mathrm{pH} \) from \( 7 \) to \( 2 \), the solubility of a sparingly soluble salt \( (\mathrm{MX}) \) of a weak acid \( (\mathrm{HX}) \) increased from \( 10^{-4} \, \mathrm{mol \, L^{-1}} \) to \( 10^{-3} \, \mathrm{mol \, L^{-1}} \). The \( \mathrm{p}K_a \) of \( \mathrm{HX} \) is:
Concentration of \( \mathrm{H_2SO_4} \) and \( \mathrm{Na_2SO_4} \) in a solution is \( 1 \, \text{M} \) and \( 1.8 \times 10^{-2} \, \text{M} \), respectively. Molar solubility of \( \mathrm{PbSO_4} \) in the same solution is \( X \times 10^{-Y} \, \text{M} \) (expressed in scientific notation). The value of \( Y \) is ________.
(Given: Solubility product of \( \mathrm{PbSO_4} \) \( (K_{sp}) = 1.6 \times 10^{-8} \). For \( \mathrm{H_2SO_4} \), \( K_{a_1} \) is very large and \( K_{a_2} = 1.2 \times 10^{-2} \))
The solubility of barium iodate in an aqueous solution prepared by mixing \( 200 \\ \mathrm{mL} \) of \( 0.010 \\ \mathrm{M} \) barium nitrate with \( 100 \\ \mathrm{mL} \) of \( 0.10 \\ \mathrm{M} \) sodium iodate is \( X \times 10^{-6} \\ \mathrm{mol \, dm^{-3}} \). The value of \( X \) is __________.
Use: Solubility product constant \( (K_{sp}) \) of barium iodate \( = 1.58 \times 10^{-9} \).
At \( 25\,^{\circ}\mathrm{C} \), the concentration of \( \mathrm{H}^{+} \) ions in \( 1.00 \times 10^{-3} \) \( \mathrm{M} \) aqueous solution of a weak monobasic acid having acid dissociation constant \( (K_a) \) of \( 4.00 \times 10^{-11} \) is \( X \times 10^{-7} \) \( \mathrm{M} \). The value of \( X \) is __________.
Use: Ionic product of water \( K_w = 1.00 \times 10^{-14} \) at \( 25\,^{\circ}\mathrm{C} \)
