Final answer:
The statement 'Alcohols with higher molecular weights tend to be less water-soluble' is true. Solubility in water decreases as the alkyl chain lengthens in alcohols because the hydrophobic character begins to outweigh the hydrophilic behavior of the hydroxyl group. Smaller alcohols can hydrogen bond with water, making them soluble, but larger ones are less so.
Step-by-step explanation:
Alcohols with higher molecular weights tend to be less water-soluble, so the statement 'Alcohols with higher molecular weights tend to be less water-soluble' is true. This decrease in solubility with increasing carbon chain length is because as the alcohol molecule becomes larger, it also becomes more hydrophobic, resembling hydrocarbons more than water-soluble molecules. The hydroxyl (-OH) group in alcohol allows for hydrogen bonding with water, which is why smaller alcohols with fewer carbon atoms, like methanol and ethanol, are completely soluble. However, for alcohols with longer aliphatic chains, like 1-decanol, the bulky nonpolar part of the molecule dominates, greatly reducing solubility in water.
Simply put, the balance between the hydrophilic (water-attracting) hydroxyl group and the hydrophobic (water-repelling) alkyl chain determines an alcohol's solubility in water. Alcohols that have a chain length of four or fewer carbon atoms are typically soluble because the hydroxyl group's effect is strong enough to enable sufficient hydrogen bonding with water. Alcohols with chains longer than four carbon atoms progressively lose their solubility due to the increased presence of the hydrophobic component.