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I know this question might be dumb but, is there an element that will go directly from solid to gas, with almost no visible or no liquid state? Just a random curious question.

I am asking if there is an element that sublimes at normal pressure and temperature.

Buck Thorn
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Danii
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  • @Danii well $\ce{CO2}$ sublimes if the pressure is below 5.1 atm. – Tyberius Jan 30 '19 at 18:30
  • Wait? Temperature? You're getting it even more muddled. You can pick only one variable here otherwise sublimation would need to be in this exact point. Carbon heated at 1 atm. to over 4000 K sublimes not melts. Arsenic does so at over 600 deg. C – Mithoron Jan 31 '19 at 19:06
  • Even though this may not be the OP's intention, I hold that is question is very relevant. I'm thinking about what's the requirement upon the interaction potential to allow a liquid state; from a thermodynamics viewpoint, this is barely a trivial question. – Gravifer May 27 '22 at 14:22

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The answer to your question is no, there is no element with no liquid state. The state of an element (or molecule) depends on the temperature and the pressure. All elements can be in any of the three states (solid, liquid or gas) with the right temperature and pressure. We say that oxygen is a gas because at standard temperature and pressure it is in gas state, but if the temperature is low enough it will condense into a liquid and if temperature is even lower it will become a solid bulk. The opposite happens when increasing temperature but of course from solid to gas.

There is a phenomenon known as sublimation, this is when a substance (carbon dioxide for example) goes directly from solid to gas, leaving no trace behind. This doesn’t mean that you cannot obtain it as a liquid, it means that at our normal pressure and temperature it will pass directly to gas, but if the conditions are different then you could have it as a liquid. I know only two elements (pure elements) that can sublimate: iodine and arsenic. But again it does not mean that they don’t have liquid state

KarlsMaranjs
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  • The answer is a bit misleading. Solid iodine will sublime as $\ce{I2}$ at "normal pressure and temperature," but at normal pressure arsenic must be heated to around 600 C. // user Mithoron also mentioned that carbon will sublime. Not sure what allotrope or at what temperature. – MaxW Jan 30 '19 at 20:51
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    Technically, carbon sublimes at atmospheric pressure. If you can get it roughly as hot as the surface of the Sun. – Oscar Lanzi Jan 30 '19 at 21:07
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    Also there is the point about pressure and the liquid phase. To my knowledge no element has any allotrope for which the critical temperature (gas to liquid limit) is lower than the melting point (solid to liquid). Thus there is some temperature and pressure at which every element will form a liquid. – MaxW Jan 30 '19 at 21:43
  • What about sulfur? – Andrew Jan 15 '22 at 20:21