Question

Normal tap water contains a small amount of dissolved oxygen. What happens to the solubility of oxygen when the water is heated?

Short answer

When water is heated, the solubility of oxygen in it decreases.

Step-by-step solution

Understanding Solubility

Solubility is the maximum amount of a substance that can be dissolved in a given amount of solvent at a specific temperature. In this case, the substance is oxygen and the solvent is water.

Understanding the Impact of Temperature on Solubility

According to scientific principles, the solubility of gases in a liquid decreases as the temperature of the liquid increases. When water is heated, the kinetic energy of water molecules increases, making it harder for the gas molecules to remain in the solution.

Conclusion

So, when water is heated, the solubility of oxygen in the water decreases. More oxygen molecules will escape from water into the air, causing the amount of oxygen dissolved in the water to decrease.

Key concepts

Dissolved Oxygen

Dissolved oxygen refers to the amount of oxygen that is present in water, in a dissolved form. It is crucial for aquatic life as fish and other organisms rely on it for respiration. The level of dissolved oxygen in water is influenced by a number of factors, including temperature, air mixing, and water movement.
In the presence of air, oxygen molecules dissolve in water through natural processes. This dissolved form is essential because it allows life to thrive in aquatic environments. It also affects the water's overall quality and health. Understanding how dissolved oxygen works is fundamental, especially when analyzing changes in environmental conditions, such as temperature.

• Essential for aquatic organisms' survival
• Influenced by water conditions and environmental changes

Temperature Effect

The temperature of water plays a significant role in determining the level of dissolved oxygen. As the temperature rises, water molecules move more energetically. This increased kinetic energy makes it difficult for gas molecules, like oxygen, to remain mixed in the water.
When water is heated, its capacity to hold dissolved gases decreases. This is because the increased motion allows gas molecules to escape more easily into the atmosphere. It's important to consider this effect when discussing ecosystems where precise oxygen levels are needed for life sustainability.

• Warmer water holds less dissolved oxygen
• Affects aquatic ecosystems and balance

Gas Solubility

Gas solubility refers to how well a gas can dissolve in a liquid. This process is influenced by several factors, with temperature being one of the most critical. When considering oxygen in water, the solubility decreases as the water's temperature rises.
Understanding how gases behave in liquids helps us predict environmental effects, especially under climate change scenarios. Knowing when and how gases dissolve or escape from water is crucial for both natural ecosystems and human activities that rely on water quality.

• Decrease in solubility with temperature increase
• Vital for predicting environmental outcomes

Water Properties

Water is a universal solvent with unique characteristics that influence its interaction with gases. Its ability to dissolve gases, salts, and other substances makes it essential for life on Earth. The inherent properties of water, including its molecular structure and physical state, determine how it dissolves gases like oxygen.
Water's unique properties, such as high surface tension and ability to balance pH, affect how it absorbs and retains oxygen. These properties are fundamental in sustaining life and must be taken into account when studying environmental impacts on water quality.

• Capable of dissolving various substances
• Affects and is affected by its environment