Cyclohexanecarboxylic acid C6H11COOH pKa 490 is only slightl

Cyclohexanecarboxylic acid, C₆H₁₁COOH (pKa 4.90), is only slightly soluble in water, but its sodium salt,C₆H₁₁COO^-Na⁺, is quite soluble in water. Describe the solubility of cyclohexanecarboxylic acid in solutions of sodium hydroxide, sodium bicarbonate (NaHCO₃), and sodium carbonate (Na₂CO₃). The pKa values for the conjugate acids of sodium hydroxide, sodium bicarbonate (NaHCO₃), and sodium carbonate (Na₂CO₃) are 15.7, 6.36, and 10.33, respectively.

Aqueous NaOH: _________soluble, insoluble, or slightly soluble

Aqueous NaHCO₃: _________soluble, insoluble, or slightly soluble

Aqueous Na₂CO₃: _________soluble, insoluble, or slightly soluble

Solution

It is given that C₆H₁₁COOH is slightly soluble in water. This is because the non-polar (hydrophobic, (C₆H₁₁)) part of the molecule is dominating over the polar part (-COOH) of the molecule. Therefore, it is partially soluble in water while the sodium salt of this molecule is ionic. therrefore, it completely soluble in water.

Aqueous NaOH : Soluble, Because it forms its sodium salt with aqueous NaOH which is soluble in water

C₆H₁₁COOH + NaOH (aq) ---> C₆H₁₁COO^-(aq) + Na⁺(aq) + H₂O(l)

Aqueous NaHCO3 : Soluble because the corboxylic group forms sodium salt which is water soluble.

C₆H₁₁COOH + NaHCO₃ (aq) ---> C₆H₁₁COO^-(aq) + Na⁺(aq) + CO₂(g) + H₂O(l)

Aqueous Na₂CO₃: Soluble because the molecule forms sodium salt with Aqueous Na₂CO₃

2C₆H₁₁COOH + Na₂CO₃(aq) --->2 C₆H₁₁COO^-(aq) + 2Na⁺(aq) + CO₂(g) + H₂O(l)