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. 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.