Would you expect 1-propanol to be soluble in water? Would you expect 1-heptanol to be soluble in water? Would either of them be more soluble in hexane than in water? Explain.ÂÂ
Would you expect 1-propanol to be soluble in water? Would you expect 1-heptanol to be soluble in water?ÂÂ
Would either of them be more soluble in hexane than in water? Explain.ÂÂ
The Correct Answer and Explanation is :
Answer:
1-Propanol is soluble in water, but 1-heptanol is only partially soluble. Both alcohols are more soluble in hexane than in water.
Explanation:
1-Propanol (CH₃CH₂CH₂OH) is a three-carbon alcohol with a hydroxyl group (-OH) at one end. The hydroxyl group can form hydrogen bonds with water molecules, which makes 1-propanol soluble in water. The nonpolar alkyl chain (three carbons) also interacts with water but to a lesser extent. The hydrophilic nature of the hydroxyl group generally outweighs the hydrophobic nature of the alkyl chain, so 1-propanol is highly soluble in water. However, its solubility may decrease slightly as the carbon chain length increases beyond 3-4 carbons.
1-Heptanol (C₇H₁₅OH) is a seven-carbon alcohol with a hydroxyl group at one end. Like 1-propanol, the hydroxyl group can form hydrogen bonds with water molecules, but the longer nonpolar carbon chain (7 carbons) creates more hydrophobic interactions that resist solubility. While 1-heptanol is slightly soluble in water, its longer alkyl chain makes it less soluble compared to 1-propanol.
In hexane, a nonpolar solvent, both alcohols are more soluble than in water. Hexane’s nonpolar nature allows it to interact better with the nonpolar alkyl chains of both 1-propanol and 1-heptanol, making them more soluble in hexane than in water. The alkyl chains of these alcohols can interact with the hydrophobic parts of hexane through van der Waals forces, while the polar hydroxyl group in 1-propanol also interacts with hexane through weaker dipole interactions, promoting some solubility. However, the solubility of 1-heptanol in hexane is significantly higher due to its larger nonpolar surface area.
In conclusion, both alcohols are more soluble in hexane than in water, but 1-propanol is more soluble in water than 1-heptanol due to its shorter alkyl chain.