Final answer:
Compared to cooler water, warmer water can hold less dissolved oxygen due to decreased solubility with increasing temperature, impacting aquatic life by reducing oxygen availability.
Step-by-step explanation:
Compared to a cooler water sample, warmer water cannot hold as much dissolved oxygen. This is due to the fact that the solubility of gases, including oxygen, decreases as the temperature of water increases. When water warms, the increased movement of water molecules forces the dissolved gases out, which can lead to oxygen depletion in natural waters. This can result in negative impacts on aquatic life, such as large-scale fish kills, due to lower oxygen availability. Furthermore, the density of water decreases as it warms, causing it to become less dense compared to cooler water.