The solubility of ${\mathrm{A}}_2{\mathrm{X}}_3$ is y mol dm^-3. Its solubility product is

1. $6<mspace\; width="1em"></mspace>{\mathrm{y}}^4$

2. $64<mspace\; width="1em"></mspace>{\mathrm{y}}^4$

3. $36<mspace\; width="1em"></mspace>{\mathrm{y}}^5$

4. $108<mspace\; width="1em"></mspace>{\mathrm{y}}^5$

In the exothermic reaction of oxidizing SO₂ by O₂ to SO₃, what factors determine the maximum yield of SO₃?

The pK_a of HCN is 9.30. The pH of a solution prepared by mixing 2.5 moles of KCN and 2.5 moles of HCN in water and making up the total volume to 500 ml will be:

The precipitate of CaF₂ $({\mathrm{K}}_{\mathrm{sp}}=1.7\times {10}^{-10})$ is obtained when equal volumes of the following are mixed

1. ${10}^{-2}<mspace\; width="1em"></mspace>\mathrm{M}<mspace\; width="1em"></mspace>{\mathrm{Ca}}^{2+}+{10}^{-3}<mspace\; width="1em"></mspace>{\mathrm{MF}}^{-}$

2. ${10}^{-3}<mspace\; width="1em"></mspace>\mathrm{M}<mspace\; width="1em"></mspace>{\mathrm{Ca}}^{2+}+{10}^{-5}<mspace\; width="1em"></mspace>{\mathrm{MF}}^{-}$

3. ${10}^{-4}<mspace\; width="1em"></mspace>\mathrm{M}<mspace\; width="1em"></mspace>{\mathrm{Ca}}^{2+}+{10}^{-4}<mspace\; width="1em"></mspace>{\mathrm{MF}}^{-}$

4. ${10}^{-5}<mspace\; width="1em"></mspace>\mathrm{M}<mspace\; width="1em"></mspace>{\mathrm{Ca}}^{2+}+{10}^{-3}<mspace\; width="1em"></mspace>{\mathrm{MF}}^{-}$

The following equilibrium is established when hydrogen chloride is dissolved in acetic acid:

$$\(\small {\mathrm{HCl}+\mathrm{CH}_3 \mathrm{COOH} \rightleftharpoons \mathrm{Cl}^{-}+\mathrm{CH}_3 \mathrm{COOH}_2^{+}}\)

The set that characterizes the conjugate acid-base pair is:

If ${\mathrm{pK}}_{\mathrm{b}}$ for fluoride ion at $25°\mathrm{C}$ is 10.83, the ionization constant of hydrofluoric acid at this temperature is

1. $1.74\times {10}^{-5}$

2. $3.52\times {10}^{-3}$

3. $6.75\times {10}^{-4}$

4. $5.38\times {10}^{-2}$

Which of the following is an example of a reversible reaction?

What is the decreasing order of strength of the bases?

${\mathrm{OH}}^{-},<mspace\; width="1em"></mspace>{\mathrm{NH}}_2^{-},<mspace\; width="1em"></mspace>\mathrm{H}-\mathrm{C}\equiv {\mathrm{C}}^{-}<mspace\; width="1em"></mspace>\mathrm{and}<mspace\; width="1em"></mspace>{\mathrm{CH}}_3-{\mathrm{CH}}_2^{-}?$

1. ${\mathrm{CH}}_3-{\mathrm{CH}}_2^{-}>{\mathrm{NH}}_2^{-}>\mathrm{H}-\mathrm{C}\equiv {\mathrm{C}}^{-}>{\mathrm{OH}}^{-}$

2. $\mathrm{H}-\mathrm{C}\equiv {\mathrm{C}}^{-}>{\mathrm{CH}}_3-{\mathrm{CH}}_2^{-}>{\mathrm{NH}}_2^{-}>{\mathrm{OH}}^{-}$

3. ${\mathrm{OH}}^{-}>{\mathrm{NH}}_2^{-}>\mathrm{H}-\mathrm{C}\equiv {\mathrm{C}}^{-}>{\mathrm{CH}}_3-{\mathrm{CH}}_2^{-}$

4. ${\mathrm{NH}}_2^{-}>\mathrm{H}-\mathrm{C}\equiv {\mathrm{C}}^{-}>{\mathrm{OH}}^{-}>{\mathrm{CH}}_3-{\mathrm{CH}}_2^{-}$

A certain weak acid has a dissociation constant of $1.0\times {10}^{-4}.$ The equilibrium constant for its reaction with a strong base is

1. $1.0\times {10}^{10}$

2. $1.0\times {10}^{14}$

3. $1.0\times {10}^{-10}$

4. $1.0\times {10}^{-4}$