The pOH of a solution at 25 °C that contains 1×10^-10 M of hydronium ions is:

The compound that gives a pair of enantiomorphs is:
(en = NH₂ CH₂CH₂ NH₂)

1. $\left[Co\right(N{H}_3{)}_{4}C{l}_2]N{O}_2$

2. $\left[Cr\right(N{H}_3{)}_6\left]\right[Co\left(CN{)}_6\right]$

3. $\left[Co\right(en{)}_{2}C{l}_2]Cl$

4. $\left[Pt\right(N{H}_3{)}_4\left]\right[PtC{l}_6]$

The correct order of increasing thermal stability of K₂CO₃, MgCO₃, CaCO₃, and BeCO₃ is:

1. $BeC{O}_3<MgC{O}_3<K_{2}C{O}_3<CaC{O}_3$

2. $BeC{O}_3<MgC{O}_3<CaC{O}_3<K_{2}C{O}_3$

3. $MgC{O}_3<BeC{O}_3<CaC{O}_3<K_{2}C{O}_3$

4. $K_{2}C{O}_3<MgC{O}_3<CaC{O}_3<BeC{O}_3$

A weak acid, HA, has a K_a of 1.00×10^-5. If 0.100 mole of this acid is dissolved in one litre of water, the percentage of acid dissociated at equilibrium is closest to:

1. 99.0%

2. 1%

3. 99.9%

4. 0.100%

The number of moles of KMnO₄ that will be needed to react with one mole of sulphite ion in an acidic solution is:

Identify the incorrect statement among the following:

Among the following, the most characteristic oxidation states for lead and tin are, respectively:

1. +4, +2

2. +2, +4

3. +4, +4

4. +2, +2

Find the correct increasing order of C–O bond length among CO, CO₃²⁻ , and CO₂:

What is the correct sequence of acidity for the following compounds?

The following equilibrium constants are given: 
N₂ + 3H₂ ⇌ 2NH₃; K₁ 
N₂ + O₂ ⇌ 2NO; K₂ 
H₂ + 1/2O₂ ⇌ H₂O; K₃ 

The equilibrium constant for the oxidation of NH₃ by oxygen to give NO is:

1. $K_2{K}_3^2/K_1$

2. $K_2{K}_3^3/K_1$

3. $K_2^2{K}_3/K_1$

4. $K_1{K}_2/K_3$