# Pressure in a liquid without gravity

Say there was a container filled with liquid floating in space. What would the pressure of the liquid be? Also would it be affected by the temperature of the liquid? I would assume so since faster moving particles would hit the walls of the container with more force.

The reason I'm asking is because with gases you have the ideal gas law where the temperature, pressure, and concentration of the gas are all related to each other. However, in liquids the only calculation for pressure in a static liquid is found by the formula for hydrostatic pressure. Therefore, a non moving liquid in space would have a pressure of 0 which is extremely counterintuitive since the molecules in the liquid would still be impacting the surface of the container.

What really got me thinking about this was the concept of osmotic pressure. Apparently, the osmotic pressure of blood can be as high as 8atm. This osmotic pressure is affected by the temperature and concentration of the solute in a similar manner as the ideal gas law. Therefore, it's incredibly intuitive that blood would have such a high osmotic pressure since the solute concentration would usually be much higher than that of gas at SATP. Now what is unintuitive is that in order for water to reach a pressure of 8atm there must be a column of it 80m high while it's concentration (density) is much higher than that of solutes in a typical solution. Where does my misunderstanding lie?

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Andy Resnick