Correcting for room temperature and atmospheric pressure

[iyun]

1. I would like to convert 1 milligram of water to mililitres at room temperature and atmospheric pressure
I know that they are equivalent at3.93 celsius and an air pressure of 1013.25kPa

Homework Equations

1mg=1ml at 3.93 celsius and 1013 kPa

The Attempt at a Solution

unsure

 

[rootX]

1. I would like to convert 1 milligram of water to mililitres at room temperature and atmospheric pressure
I know that they are equivalent at3.93 celsius and an air pressure of 1013.25kPa

Homework Equations

1mg=1ml at 3.93 celsius and 1013 kPa

The Attempt at a Solution

unsure

ever heard of this formula:
PV=nRT?

use it!

 

[rootX]

oops... that was for gases lol

there might be some for liquids

try assuming that there's a linear relationship ...
so T1/something = T2/something

 

[hage567]

Look up a density table for water.

 

[iyun]

Im unclear on T1/something=T2/something
there's just one temperature here -water at room temperature
thanks

 

[mgb_phys]

You need a table of the density of water at different temperatures, the pressure is only going to have a very small effect.
There is no law for this as such it is an experimental measurement.

 

[iyun]

how does density play into the equation?

 

[mgb_phys]

The density of water chnages with temperature in a rather unusual way.
The maximum density is at just under 4degC, hotter than that water expands slightly so your 1mg of water will take up slightly more than 1ml of volume at room temperature.
As I said there isn't a law predicting this although there are probably equations which are fits to the experimental data. It certainly isn't linear.

 

[rootX]

yes, mgb_phys is right.
http://www.simetric.co.uk/si_water.htm

there's the table.