Can All Solids Be Liquefied by Increasing Pressure?

[Intr3pid]

Homework Statement

Which of the following solid substances can be liquefied simply by increasing the pressure suffciently?
ice (H2O)
diamond (C)
dry ice (CO2)
sulfur (S)
graphite (C)

Which of the following substances cannot be liquified at 1 atm pressure?
nitrogen (N2)
helium (He)
hydrogen (H2)
water (H2O)
carbon dioxide (CO2)

Homework Equations

The Attempt at a Solution

I know that some of them are solids, liquids and gases in standard state but I don't know which can be liquified etc. help?

 

[Borek]

In general, you will need phase diagrams for these. And without temperature given first question can't be answered. See water phase diagram:

http://www.lsbu.ac.uk/water/phase.html

 

[Blueshift5]

I would approach this question by first considering the properties of each substance and how they relate to their ability to be liquefied.

Ice (H2O) is a solid substance that can be liquefied by increasing the pressure, as demonstrated by the phase diagram of water. This is because increasing the pressure causes the molecules to come closer together, making it easier for them to move past each other and form a liquid.

Diamond (C) is a covalent network solid, meaning the carbon atoms are bonded together in a continuous network. This makes it difficult to liquefy, as the strong covalent bonds must be broken in order to allow the molecules to move freely.

Dry ice (CO2) is a solid form of carbon dioxide and can be liquefied by increasing the pressure. This is because carbon dioxide is a gas at standard pressure and temperature, but when enough pressure is applied, it can be forced into a liquid state.

Sulfur (S) is a molecular solid and can be liquefied by increasing the pressure. Similar to ice, increasing the pressure causes the molecules to come closer together, allowing them to move past each other and form a liquid.

Graphite (C) is a layered molecular solid and can be liquefied by increasing the pressure. The layers in graphite are held together by weak intermolecular forces, so increasing the pressure can cause the layers to slide past each other and form a liquid.

As for the second question, all of the substances listed can be liquefied at 1 atm pressure except for helium (He). Helium is a noble gas and has a very low boiling point, so it remains in a gaseous state even at 1 atm pressure. Nitrogen (N2), hydrogen (H2), water (H2O), and carbon dioxide (CO2) can all be liquefied at 1 atm pressure by lowering the temperature below their respective boiling points.