Quiz 2 - Chemical Reactions and Properties of Solutions | Chemical Reactions and Properties of Solutions

CH₃​COOH (acetic acid) is a weak electrolyte because it partially dissociates into CH₃COO⁻ and H⁺ ions in solution.

In KClO₃​, potassium has an oxidation state of +1, and oxygen has an oxidation state of -2. The oxidation state of chlorine is calculated as follows:
KClO₃: +1 + x + 3 x (−2) = 0 ⇒ x = +5

A strong acid completely ionizes in solution, releasing all its H⁺ ions.

The balanced redox reaction in acidic solution is: MnO₄⁻ + 5 Fe²⁺ + 8 H⁺ → Mn²⁺ + 5 Fe³⁺ + 4 H₂O

The balanced redox reaction in a basic solution is: MnO₄⁻ + C₂O₄²⁻ + 2 H₂O → MnO₂ + 2 CO₂ + 4 OH^-

NaCl is a strong electrolyte and completely dissociates into Na⁺ and Cl⁻ ions, providing high electrical conductivity.

The ionic strength I is calculated using the formula I = $\frac{1}{2}$ $\sum _{\mathrm{i} = 1}^{\mathrm{n}} {\mathrm{c}}_{\mathrm{i}}{{\mathrm{z}}_{\mathrm{i}}}^2$

Na₂SO₄ → 2 Na⁺ + SO₄^2-, therefore:

• Na⁺ has c = 2 x 0.2 M = 0.4 M and z = +1
• SO₄^2- has c = 0.2 M and z = -2

I = $\frac{1}{2}$ [0.4 x 1 + 0.2 x 4] = 0.6 M

The solubility of most solid solutes, including KNO₃​ (potassium nitrate), in water increases with an increase in temperature.

Hexane is a nonpolar solvent and is best suited for dissolving nonpolar solutes like iodine (I₂​), following the "like dissolves like" principle.

The mole fraction of NaCl is given by $\frac{\mathrm{moles} \mathrm{of} \mathrm{NaCl}}{\mathrm{total} \mathrm{moles}}$ = $\frac{2}{2 + 8}$ = 0.2