When temperature increases dissolved oxygen of water

Options

A. increases
B. decreases
C. remain same
D. first increases, then decreases

Answer

### Step-by-Step Solution:

1. **Understanding Dissolved Oxygen**: Dissolved oxygen (DO) is the amount of oxygen that is present in water. It is crucial for the survival of aquatic organisms such as fish and invertebrates.

2. **Temperature and Solubility**: The solubility of gases in liquids, including oxygen in water, is influenced by temperature. Generally, as the temperature of water increases, the solubility of oxygen decreases.

3. **Effect of Temperature Increase**: When the temperature of water rises, the kinetic energy of the water molecules increases. This increased movement makes it harder for oxygen molecules to remain dissolved in the water.

4. **Impact on Aquatic Life**: As the dissolved oxygen levels decrease due to rising temperatures, aquatic life that depends on oxygen for survival may begin to suffer. This can lead to a decrease in fish populations and other marine organisms.

5. **Conclusion**: Therefore, when the temperature increases, the dissolved oxygen in water decreases.

### Final Answer:
When temperature increases, dissolved oxygen in water decreases.

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