For each solute, identify the better solvent: water or hexane.
Water, H2O
Hexane, C6H14
Answer Bank
CO
1
CHÚNH
NH3
NO
B
The Correct Answer and Explanation is:
To determine whether water or hexane is a better solvent for each solute, it is important to consider the principle “like dissolves like,” which means that polar solutes dissolve better in polar solvents, and nonpolar solutes dissolve better in nonpolar solvents.
Solute: CO (Carbon Monoxide)
- Better Solvent: Water
- Explanation: Carbon monoxide (CO) is a polar molecule. Water (H₂O) is also polar due to the hydrogen bonding between molecules. The dipole-dipole interactions between CO and water make water a better solvent for CO. Hexane, on the other hand, is nonpolar, and polar molecules like CO do not interact well with nonpolar solvents.
Solute: CH₃OH (Methanol)
- Better Solvent: Water
- Explanation: Methanol (CH₃OH) is a polar molecule, with both a hydroxyl group (-OH) capable of hydrogen bonding and a methyl group (-CH₃) that is nonpolar. Because water is also polar and can form hydrogen bonds, it is able to dissolve methanol effectively. Hexane, being nonpolar, is less likely to interact with methanol’s polar portion.
Solute: NH₃ (Ammonia)
- Better Solvent: Water
- Explanation: Ammonia (NH₃) is a polar molecule and can form hydrogen bonds with water molecules. Since water is a highly polar solvent, it will be a better solvent for ammonia compared to hexane, which does not interact well with polar molecules.
Solute: NO (Nitric Oxide)
- Better Solvent: Water
- Explanation: Nitric oxide (NO) is a polar molecule, and water is highly polar as well. The dipole-dipole interactions between NO and water make water the better solvent. Hexane, being nonpolar, does not interact well with polar molecules like NO, making it a poor choice for this solute.
Conclusion:
Water is the better solvent for all of the listed solutes (CO, CH₃OH, NH₃, NO) due to its polar nature and ability to form hydrogen bonds. Hexane, being nonpolar, is not effective in dissolving these polar solutes.