Question for Claude

[jon-nyc]

What are farts composed of?

Farts are primarily composed of five gases:

Nitrogen (N₂) — the dominant component, typically 20–90% of total volume. Most comes from swallowed air.

Hydrogen (H₂) — produced by gut bacteria fermenting carbohydrates. Can make up 0–50%.

Carbon dioxide (CO₂) — also from bacterial fermentation and swallowed air. Typically 10–30%.

Methane (CH₄) — produced by a specific subset of gut bacteria (Methanobrevibacter smithii). Only about 1/3 of people are “methane producers”; for them it can be 0–26%.

Oxygen (O₂) — small amounts from swallowed air, usually less than 10%.

The smelly stuff — the odor comes from trace compounds (typically under 1% total), mainly hydrogen sulfide (H₂S), methanethiol, dimethyl sulfide, and short-chain fatty acids. These are produced by bacteria breaking down sulfur-containing proteins..

Are they heavier than air?

Are farts heavier than air?

It depends on the mix, but on average, farts are roughly similar to air in density, and often slightly lighter. Here’s why:

∙ Air has an average molecular weight of about 29 g/mol
∙ The main fart gases: N₂ = 28, H₂ = 2, CO₂ = 44, CH₄ = 16
∙ A typical mix is dominated by N₂ and H₂, which are both lighter than air (especially H₂, which is extremely light)
∙ CO₂ is heavier than air (MW 44), but it’s usually a minority component

So a typical fart, being rich in nitrogen and hydrogen, tends to be slightly lighter than air — which is part of why it rises. However, a fart with a high CO₂ content could be close to air density or slightly heavier. Methane is also lighter than air (MW 16), so methane-rich farts are definitely buoyant.

In short: farts generally float upward, which your nose can confirm.​​​​​​​​​​​​​​​​

[Axtremus]

You cross-check Claude's response with other models'?