# Highest Expansion Ratio?

1. Dec 15, 2009

### samblohm

What substance has the highest expansion ratio? (liquid:gas)

2. Dec 16, 2009

### Staff: Mentor

Assuming ideal gas - will the volume of the substance after it was converted to gaseous form depend on the substance?

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methods

Last edited: Dec 17, 2009
3. Dec 16, 2009

### samblohm

I know water has an expansion ratio of 1:1700, and neon's is 1:1400 (which is the highest for elemental substances).

4. Dec 17, 2009

### Staff: Mentor

On the second thought - question is no clear. It doesn't state anything about temperature. If the idea is that it is measured at STP many substances are ruled out, even if they have (in their temperature range) much higher expansion ratio.

And neon doesn't look to me like a possible record holder (even for elemental substances at STP). For example xenon seems to be a tiny bit better (and I am not stating it is Xe that wins in this category).

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5. Dec 17, 2009

### samblohm

What I mean is the volume of a substance just below its boiling point (at 1 atm) compared to the volume of the substance right after it has all boiled to a gas (at 1 atm)

6. Dec 17, 2009

### Staff: Mentor

This is still not clear. You can't compare water (boils at 100 deg C) with iron (boils around 2900 deg C) even if they can be both converted to gaseous form. For obvious reasons 1 mole of gas at 2900 deg C will have much higher volume.

7. Dec 17, 2009

### samblohm

Which is why i'm not comparing their volume. I'm comparing the ratio of their liquid volume to gas volume.

8. Dec 17, 2009

### Staff: Mentor

The problem hasn't gone away - gases expand a lot more with temperature than liquids do, so liquids with higher boiling points are likely to score higher on your scale. Knowing the purpose and constraints would certainly help us a lot.

You can certainly google for whatever info you want and build a table of whatever you really want, though.

Last edited: Dec 17, 2009