The self-ionization constant for pure formic acid, K = [\(H C O O H_{2}^{+} \left]\right. \left[\right. H C O O^{-} \left]\right.\) ] has been estimated as \(\left(10\right)^{- 4}\) at room temperature. The percentage of formic acid molecules in pure formic acid that are converted to formate ions is

\(\left(\right. Given : d_{HCOOH} = 1 . 22\ g / cc \left.\right)\)

1. 0.0185%

2. 0.0073%

3. 0.074%

4. 0.037%

AgOH is added to NaCl solution to form AgCl precipitate. After the precipitation, the pH of the solution is 8. The [Cl^-] is $({\mathrm{K}}_{\mathrm{sp}} \mathrm{of} \mathrm{AgCl}={10}^{-12}, {\mathrm{K}}_{\mathrm{sp}} \mathrm{of} \mathrm{AgOH}={10}^{-10})$

1. ${10}^{-6} \mathrm{M}$

2. ${10}^{-4} \mathrm{M}$

3. ${10}^{-8} \mathrm{M}$

4. ${10}^{-10} \mathrm{M}$

For the reaction 
${\left[\mathrm{Ag}{\left(\mathrm{CN}\right)}_2\right]}^{-}\left(\mathrm{aq}\right)\rightleftharpoons {\mathrm{Ag}}^{+}\left(\mathrm{aq}\right)+2{\mathrm{CN}}^{-}\left(\mathrm{aq}\right),$the equilibrium constant at $25°\mathrm{C}$ is $4.0\times {10}^{-19}.$ The silver ion concentration in a solution that was originally 0.10 M in KCN and 0.03 M in AgNO₃ will be:

1. $2.5\times {10}^{-18} \mathrm{M}$

2. $1.5\times {10}^{-18} \mathrm{M}$

3. $5.5\times {10}^{-18} \mathrm{M}$

4. $7.5\times {10}^{-18} \mathrm{M}$

Separate solutions of four sodium salts NaW, NaX, NaY and NaZ had pH 7.0, 9.0, 10.0 and 11.0 respectively. When each solution is 0.1 M, the strongest acid is

1. HW

2. HX

3. HY

4. HZ

Silver acetate is a slightly soluble salt of a weak acid $({\mathrm{K}}_{\mathrm{a}}=1.75\times {10}^{-5})$. At $25°\mathrm{C}$, 100 g of water dissolves 1.04 g of crystalline silver acetate. The density of saturated solution of silver acetate at $20°\mathrm{C}$ is 1.01 g/cc. The solubility product constant for silver acetate at $20°\mathrm{C}$

1. $2.43\times {10}^{-3}$

2. $3.87\times {10}^{-3}$

3. $7.74\times {10}^{-5}$

4. $1.35\times {10}^{-5}$

0.1 M solution of three different sodium salts NaX, NaY and NaZ have pH values 7.0, 9.0 and 11.0 respectively. The correct order of dissociation constant values of these acids is

1. K_HX<K_HY<K_HZ

2. K_HX>K_HY>K_HZ

3. K_HX>K_HZ>K_HY

4. K_HX<K_HY<K_HZ

When equal volume of the following solutions are mixed, which of the following gives maximum precipitate? $({\mathrm{K}}_{\mathrm{sp}} \mathrm{of} \mathrm{AgCl}={10}^{-12})$

1. ${10}^{-4} \mathrm{M}\hspace{0.17em}{\mathrm{Ag}}^{+} \mathrm{and} {10}^{-4} \mathrm{M} {\mathrm{Cl}}^{-}$

2. ${10}^{-3} \mathrm{M}\hspace{0.17em}{\mathrm{Ag}}^{+} \mathrm{and} {10}^{-3} \mathrm{M} {\mathrm{Cl}}^{-}$

3. ${10}^{-5} \mathrm{M}\hspace{0.17em}{\mathrm{Ag}}^{+} \mathrm{and} {10}^{-5} \mathrm{M} {\mathrm{Cl}}^{-}$

4. ${10}^{-6} \mathrm{M}\hspace{0.17em}{\mathrm{Ag}}^{+} \mathrm{and} {10}^{-6} \mathrm{M} {\mathrm{Cl}}^{-}$

The percentage hydrolysis of NaCN in $\left(\frac{\mathrm{N}}{80}\right)$ aqueous solution [Dissociation constant of HCN is $1.3\times {10}^{-9}$ and ${\mathrm{K}}_{\mathrm{w}}=1.0\times {10}^{-14}$] is

1. 8.2

2. 9.6

3. 5.26

4. 2.48

Hydrolysis constant K_A and K_B of two salts of weak acids HA and HB
are 10^-8 and 10^-6 respectively. If the dissociation constant of the third acid HC is 10^-2. The order of acidic strengths of three acids will be

1. HA>HB>HC

2. HB>HA>HC

3. HC>HA>HB

4. HA=HB=HC

A solution containing NH₄Cl and NH₄OH has a hydroxide ion concentration of ${10}^{-6} \mathrm{mol} {\mathrm{litre}}^{-1}$, which of the following hydroxides could be precipitated when this solution is added in equal volume to a solution containing 0.1 M of metal ions?

1. $\mathrm{AgOH} ({\mathrm{K}}_{\mathrm{sp}}=5\times {10}^{-3})$

2. $\mathrm{Cd}{\left(\mathrm{OH}\right)}_2 ({\mathrm{K}}_{\mathrm{sp}}=8\times {10}^{-6})$

3. $\mathrm{Mg}{\left(\mathrm{OH}\right)}_2 ({\mathrm{K}}_{\mathrm{sp}}=3\times {10}^{-11})$

4. $\mathrm{Fe}{\left(\mathrm{OH}\right)}_2 ({\mathrm{K}}_{\mathrm{sp}}=8\times {10}^{-16})$