Boyle's law is obeyed by

Options

A. Real gas of constant mass and temperature
B. Ideal gas of constant mass and temperature
C. Both ideal and real gases at constant temperature and variable mass
D. Both ideal and real gases of constant mass and variable temperature.

Answer

### Step-by-Step Solution:

1. **Understanding Boyle's Law**:
Boyle's Law states that for a given mass of gas at constant temperature, the volume (V) of the gas is inversely proportional to the pressure (P). This can be mathematically expressed as:
\[ PV = k \]
where \( k \) is a constant.

2. **Conditions for Boyle's Law**:
- The temperature must remain constant.
- The mass of the gas must be fixed.
- The gas should ideally behave like an ideal gas.

3. **Ideal vs. Real Gases**:
- Ideal gases perfectly follow Boyle's Law under all conditions.
- Real gases approximate ideal behavior under high temperatures and low pressures.

4. **Graphical Representation**:
- When plotting pressure (P) against volume (V), the relationship is hyperbolic.
- As the volume increases, the pressure decreases, demonstrating the inverse relationship.

5. **Experimental vs. Theoretical Values**:
- At low temperatures, real gases deviate from the ideal behavior.
- As the temperature increases, real gases start to behave more like ideal gases, thus obeying Boyle's Law more closely.

6. **Conclusion**:
- Boyle's Law is primarily valid for ideal gases, but real gases can also obey it under certain conditions (high temperature and low pressure).
- Therefore, the answer to the question "Boyle's law is obeyed by" is that it is obeyed by ideal gases and, under specific conditions, real gases.