A fish dies when it is put in an boiled water but cooled to room temperature. This happens because the water in the aquarium is

Options

A. unfit for swimming by fish
B. depleted In oxygen
C. unfit for drinking by fish
D. depleted In minerals

Answer

To solve the question regarding why a fish dies when placed in boiled water that has cooled to room temperature, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Environment**:
- When water is boiled, it reaches a temperature of 100 degrees Celsius (212 degrees Fahrenheit). This process involves heating the water to a point where it turns into steam, which can lead to significant changes in the water's composition.

2. **Oxygen Content in Water**:
- One of the critical aspects of water is its ability to hold dissolved oxygen, which is essential for fish survival. When water is boiled, the high temperature causes a significant reduction in the amount of dissolved oxygen present in the water.

3. **Cooling the Boiled Water**:
- After boiling, if the water is allowed to cool down to room temperature, it may appear normal to the naked eye. However, the crucial factor is that the oxygen content remains low because boiling has already driven off a substantial amount of dissolved oxygen.

4. **Impact on Fish**:
- Fish rely on dissolved oxygen in the water to breathe. When they are placed in water that has been boiled and cooled, the lack of sufficient oxygen leads to suffocation, resulting in the death of the fish.

5. **Conclusion**:
- Therefore, the reason the fish dies in boiled water that has cooled to room temperature is that the water is depleted in oxygen, making it unfit for the fish to survive.

### Final Answer:
The water in the aquarium is depleted in oxygen.

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