system
Given the following post, respond as if you're commenting on Reddit:
human
Do different gases convect heat at different rates?

Metal and wood conduct heat at two different rates, but do gases behave the same?  If there is a difference, would the effect be noticeable by touch?
gpt
Heat transfer due to natural convection is not trivial, and there are many different, generally empirical, approximations that apply in different circumstances (see Nusselt number).

In general there are a few material properties that affect the rate of convection and resulting heat transfer:

\- Thermal expansion coefficient. The more a fluid expands as it warms the greater the buoyancy force, which is the driver of natural convection.

\- Thermal diffusivity. If heat diffuses (conducts) easily through the fluid then there won't be strong thermal gradients to drive convection.

\- Viscosity. Clearly convection involves mixing of fluid and so viscosity is relevant. Viscosity of gasses is lower than liquids so perhaps less important for the former.

It would certainly be possible to set up scenarios where certain gasses would generate strong convection currents and others would generate noticeably weaker ones.