Viewing a single comment thread. View all comments

Solarisphere t1_j2a5xx5 wrote

Reply to comment by PeachSnappleOhYeah in TIL Snow is an excellent insulator because it consists of about 90–95 percent trapped air (fresh). This is the reason why igloos are warmer inside than outside, and why some animals in colder regions build snow caves to spend the winter while hibernating. by SunCloud-777

This is wrong in at least four different ways:

  1. You're conflating thermal conductivity, specific heat capacity, and latent heat of fusion.
  2. If conductivity was the main factor in keeping drinks cool (it's not), then a low conductivity would mean ice is bad at cooling drinks.
  3. The amount of energy required to heat or cool a substance is the heat capacity, not conductivity. It is more right to say that's the reason ice is good at cooling drinks, but it's still not correct.
  4. Ice "wanting to stay ice" is the latent heat of fusion. To melt ice, you pump heat into it and yet it doesn't change temperature until it's fully melted. This is distinct from heat capacity since there is no temperature change. Ice has a high latent of fusion (even higher than many metals), and that is why it's good at keeping your drink cold. Ice can stay cold (and therefore maintain the ΔT necessary for heat transfer) while pulling heat out of the drink.
1