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

To solve the question "Boyle's law is obeyed by," we will follow these steps:

### Step 1: Understand Boyle's Law
Boyle's Law states that for a given amount of gas at a constant temperature, the pressure (P) of the gas is inversely proportional to its volume (V). This can be mathematically expressed as:
\[ P \propto \frac{1}{V} \]
or
\[ PV = k \]
where \( k \) is a constant.

### Step 2: Identify Conditions for Boyle's Law
For Boyle's Law to hold true, two conditions must be satisfied:
1. The temperature of the gas must remain constant (isothermal conditions).
2. The mass of the gas must remain constant.

### Step 3: Determine Which Gases Obey Boyle's Law
Boyle's Law is obeyed by:
- **Ideal Gases**: These gases perfectly follow the gas laws under all conditions.
- **Real Gases**: Real gases can also obey Boyle's Law, but typically only under low pressure and high temperature conditions where they behave more like ideal gases.

### Step 4: Conclusion
Based on the understanding of Boyle's Law and the conditions under which it is applicable, we can conclude that:
- The correct answer to the question "Boyle's law is obeyed by" is **ideal gases** and **real gases at low pressure**.

### Final Answer
Boyle's law is obeyed by ideal gases and real gases at low pressure.

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