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  2. At what pressure will hydrogen start to liquefy at room...

    chemistry.stackexchange.com/questions/140496/at-what...

    The pressure required to reach this point is called the critical pressure which, for hydrogen, is $\pu{1.239 MPa} = \pu{179.7 psi}$. Hence, while you can't change hydrogen into a liquid at room temperature, you can change it into a (supercritical) fluid. Incidentally, there are two established storage technologies for pure hydrogen in vehicles.

  3. hydrogen bond - Why H2O is a liquid (water) and H2S is a gas ...

    chemistry.stackexchange.com/questions/86540

    Well, first of all depends on what temperature you are considering. But let’s take room temperature (20 degrees). In Water, the oxygen atom is highly electronegative and can polarize (partially) the hydrogen atoms, thus hydrogen-hydrogen bonds between the H2O molecules can be formed creating a very high boiling point.

  4. Enthalpy of the reaction between hydrogen and oxygen

    chemistry.stackexchange.com/questions/15126/enthalpy-of...

    Therefore, the reaction must be specified for which this quantity applies. In this case, the enthalpy of 484 kJ 484 k J is released when 2 mol 2 m o l of hydrogen gas react with 1 mol 1 m o l of oxygen gas to form 2 mol 2 m o l of gaseous water: 2HX2(g) +OX2(g) 2HX2O(g) ΔH∘ = −484 kJ 2 H X 2 (g) + O X 2 (g) 2 H X 2 O (g) Δ H ∘ = − 484 ...

  5. Can a spark ignite hydrogen? - Chemistry Stack Exchange

    chemistry.stackexchange.com/questions/5421

    Yes, if the HX2(g) H X 2 (g) concentration in oxygen or air is greater than about 4% not only will it burn, but most likely explode. You should avoid all heat sources when dealing with it, including direct sunlight. Just so you know, hydrogen safety datasheets include words such as "extremely flammable" and "DANGER" in red capital letters.

  6. Which has stronger hydrogen bonds: water or ice?

    chemistry.stackexchange.com/questions/96452

    Water has stronger hydrogen bonds than ice does. Liquid water is denser than ice. Since water and ice are both made of H2O molecules, the fact that water is denser means the H2O molecules are closer together in water than they are in ice. This means the intermolecular forces attracting one H2O molecule to another must be stronger in water than ...

  7. At what temperature (in kelvin) are most of the elements on the...

    chemistry.stackexchange.com/questions/41971

    The boiling point of hydrogen is $-252.87~^{\circ}\rm C$ or $20.28\rm\,K$, which is the least boiling point so you can expect that all other elements would liquidify or solidify at or below this temperature. But the concept of phases is much more complicated than that.

  8. I'm sure most of us have heard that saturated fats are solid at room temperature, and unsaturated fats are liquid at room temperature. I'm wondering how this relates to their chemical structure -- saturated fats contain only single bonds between carbons, yet to qualify as an unsaturated fat a C=C double bond must exist.

  9. Why is CH4 a gas at room temperature but CH3Cl a liquid?

    chemistry.stackexchange.com/questions/40806

    It is a gas at room temperature with a boiling point ϑb = −23.8 ∘C ϑ b = − 23.8 ∘ C. Chloroform, which is indeed a liquid at room temperature (ϑb = 61.2 ∘C ϑ b = 61.2 ∘ C) is CHClX3 C H C l X 3 or trichloromethane. You need to substitute three hydrogens with chlorine atoms to create chloroform. Share. Cite.

  10. Effect of temperature on Hydrogen Bonding? - Chemistry Stack...

    chemistry.stackexchange.com/questions/10819

    1,151 6 15 23. Add a comment. Yes. Temperature disrupts bond of all kinds. Heat up a protein hot enough and you can even disrupt its primary structure - the linear sequence of amino acids, and amino acids are held together through covalent bonds. This is why prion contaminated organisms and instruments must be heated to extremely, extremely ...

  11. organic chemistry - Why is phenol a solid at room temperature ...

    chemistry.stackexchange.com/questions/70832/why-is-phenol...

    2. The commonly cited reason is inter-molecular hydrogen bonding. But won't the hydrogen bonding in phenol be weaker than that of most alcohols because of resonance-effect? And yet, alcohols with stronger hydrogen bonding (such as ethanol, propanol, etc.) aren't solids at room temperature. Also, if the reason behind its state is it's molecular ...