Density
Gas density @ 60°F (kg/L) = Specific Gravity @ 60°F * 0.999012
Degrees API = (141.5 / G) - 131.5
G = specific gravity (oil / water @ 60° F)
Density of water @ 15°C = 0.9991026 g/mL
Density of air (0°C, 1 atm0 = 1.2928 g/L)
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