I’ve been scratching my head (and working in ms excel) about the following for about 6 hours and would greatly appreciate it if somebody could help me.(adsbygoogle = window.adsbygoogle || []).push({});

Basically, I am trying to figure out WHY the density of water is approximately one gram per cubic centimeter (at 1 atm pressure and 4 degrees Celsius).

Note the following conversions:

1 atm = 101,325.01 Pa = 14.7 psi

4 C = 39.2 F = 277 K

Also:

Gas Law Constant = 8.3145

Starting at the molecular level, water has a molecular mass of 18.015 g/mol.

Using the ideal gas law:

density = (pressure) (molar mass) / ((temp) (8.3145))

g/m^3 = (Pa) (g/mol) / ((K) (8.3145))

This is what I come up with:

density = (101,325 Pa) (18.015 g/mol) / ((277 K) (8.3145))

density = 792.56 grams per cubic meter

792.56 grams per cubic cm does NOT equal 1 gram per cubic centimeter.

Why?

Where did I go wrong?

Any guidance is greatly appreciated.

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# Weight of water from molecular mass to grams per cubic centimeter

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