This list mentions a handful of chemicals that boil at temperatures that would be safe to the human hand; example: Ethyl bromide C2H3Br, which boils at 101F, about the temperature of a hot bath. But then again, I know nothing of chemistry, and for all I know it will cause horrible chemical burns or some other catastrophe.
Are there any liquids that a) aren’t dangerous to human skin, and b) boil at a temperature that is safe for human skin?
Pentane boils at 96 F. It’s not good for you, but it’s not going to cause acute chemical burns. Butane is 30 F, so it would be colder than icewater in liquid form but not likely to cause acute frostbite.
Yeah, with either of those the bigger risk would be from inhaling the fumes. But put a fan behind you and you’d probably be just fine.
Acetone boils at 133F and according to Wikipedia is believed to be only slightly toxic - it certainly won’t give you a chemical burn just by touching it. Breathing the fumes is definitely not recommended.
130F to 140F is about the range of home hot water heaters, so not scalding hot, but not exactly comfortable.
Being near an open container of either of these and sticking your hand in the boiling liquid will cause severe burns if you are near an open flame.
You can briefly put your hand in liquid nitrogen, protected by the Leidenfrost Effect. It will boil vigorously if you do.
Don’t try this at home.
^ Molten lead, too. Good old Leidenfrost.
You can do it with water, if it is at a sufficiently low atmospheric pressure…
I’m with John DiFool go high enough into the mountains and you’re golden, just use water. Easy peasy!
You could do dichloromethane, but I can tell you from personal experience with skin exposure it will be somewhat painful. A brief, one-time exposure won’t really hurt you. (The problem with DCM is that almost nothing stops it from penetrating, except for laminate-style materials or other massive gloves with no dexterity. It’ll go right through a disposable nitrile glove and into the skin.)
This is not correct. Skin begins to burn in the range of 110-115F. By 130 you’re going to receive a significant (though probably not catastrophic) burn.
Plus, practically speaking, as I read the question, the heat source would need to be the hand. I can’t see any way to keep something above about 95 in the hand, so we need to look at things with boiling points below that. And there will be a host of organics (of varying handling safety) in that range.
Aside: The water heater keeps the water at those temps, but there are losses along the way, and for sufficient volume you need a higher temp than is desired so that you can mix in the cold water
When you pour rubbing alcohol (or, just about any alcohol) on your hands, you experience a cooling effect. The alcohol is boiling away taking away the heat from your hands.
I hate to be that guy
You are feeling evaporative cooling, but a boiling point is a specific temperature at which the liquid rapidly forms bubbles as it vaporizes.
So don’t use an open flame to boil them. And butane’s boiling point is below room temperature, so you won’t even need a dedicated heat source; you just need to remove the container from the freezer.
It’s not boiling, it’s evaporating. Big difference.
Tangent:
This makes me wonder if there are special uses for liquid butane in Arctic/Antarctic climates that would be impractical elsewhere. Or maybe in space?
The boiling point of ethanol is 173.1F.
When you pour water on your hands you experience a cooling effect. It’s quite surprising how cold you feel when you get out of a swimming pool in the desert with air temps of 110F. But the water isn’t boiling off you.
Just in terms of temperature, you could try diethyl ether, which boils at 94 F. But there are, well, other considerations.
I don’t know of any, but there is an example of the opposite: butane cigarette lighters don’t work very well at low temperatures.
Right. If it’s below 30 F the butane won’t be at the vapor point. All these hydrocarbons need to be vaporized and mixed with oxygen before they burn like we think they should burn.