Standard boiling point of water is

Options

A. 100°C
B. 99°C
C. 99.6°C
D. 110°C

Answer

To determine the standard boiling point of water, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Concept of Boiling Point**:
The boiling point of a substance is the temperature at which it changes from the liquid phase to the gas phase. For water, this occurs when the vapor pressure of the liquid equals the atmospheric pressure.

2. **Standard Conditions**:
The standard boiling point is defined under standard atmospheric pressure, which is typically 1 atmosphere (atm) or 101.3 kPa.

3. **Heating Water**:
When we heat water, its temperature increases. For example, if we start heating water at room temperature (around 25°C), it will not boil until it reaches its boiling point.

4. **Identifying the Boiling Point of Water**:
As we continue to heat the water, we find that at 100°C (under standard atmospheric pressure), water begins to boil and convert into vapor.

5. **Conclusion**:
Therefore, the standard boiling point of water is **100°C**.

6. **Alternative Representation**:
This can also be expressed in Kelvin by adding 273 to the Celsius temperature:
\[ 100°C + 273 = 373 K \]

### Final Answer:
The standard boiling point of water is **100°C** or **373 K**.

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