Which of the following represent Gay Lussac’s law? I. P constant T II. P T P T III. P V P V Choose t — States of Matter and Gaseous State Chemistry Question

💡 Solution & Explanation

# Gay Lussac's Law Analysis **Gay Lussac's Law Statement:** At constant volume and amount of gas, pressure is directly proportional to absolute temperature. $$\frac{P}{T} = \text{constant}$$ Or: $P \propto T$ (at constant V and n) --- ## Evaluating Each Option: **I. P constant T** - This represents an inverse relationship (P decreases as T increases) - ❌ **Incorrect** — contradicts Gay Lussac's law **II. P ∝ T or $\frac{P}{T} = \frac{P'}{T'}$** - This represents direct proportionality - ✓ **Correct** — matches Gay Lussac's law exactly **III. P ∝ V or $\frac{P}{V} = \frac{P'}{V'}$** - This represents Boyle's Law (inverse relationship at constant T) - ❌ **Incorrect** — this is not Gay Lussac's law --- ## Conclusion: **Only statement II correctly represents Gay Lussac's law.** The answer is **D** (assuming D corresponds to "only II" or similar phrasing in your options).