[Quimbly]

Hi,
I was looking for some figures on the compressibility of water, and this is what I discovered: 0.46 GPa-1, c.f. CCl4 0.92 GPa-1, at 20°C.

The problem is, I don't know what it means.

GPa is a GigaPascall (1,000,000,000 Pascals), right? So, does this mean that water compresses by a factor of 0.46 under a pressure of 1 GPa?

What about all the stuff after that?

c.f. And what's this about Carbon Tetrachloride and the other number (0.92)?

Can someone please help me understand this?

Thanks in advance...

[labman]

Liquids are close to incompressible. I think the figures you have for water are right. I looked in an older handbook that used cgs units rather than SI. I am not sure why your source looks like it went on to give figures for carbon tetrachloride. In most work, the compression of liquids may be neglected.

[Quimbly]

Thanks for the reply.

Yes, this is also a problem I've discovered; In almost every source I've read on the Internet, they say that liquids are next to incompressibile.  Well, the whole point is that I am interested in HOW MUCH liquids do compress under extreme pressures.

In regards to my question, am I right in assuming that 0.46 GPa-1 means that water will compress by a volumetric factor of 0.46 under 1 GPa of pressure?

If you think the value is correct, can you verify this?  Do you have a link to some site where this is documented?  

Also, I wouldn't think that compression would be a linear function of pressure.  Is it?  If not, does anyone have a graph that shows water's (or other liquid's) volume as a function of pressure?

Thanks again!

[labman]

Go to any library and ask for the Handbook of Chemistry and Physics. It is the big green one. Look up compressibility. Most libraries will have one enough newer than mine to use SI units.

At those pressures, you also need to allow for the streching of the container.