Procedure Title: API
Instrumentation: Pycnometer
Theory of Operation:
• API is a measure of how heavy or light petroleum liquid is compared to water.
• It is an inverse measure of a petroleum liquid’s density relative to that of water (Specific Gravity).
• It is used to compare densities of petroleum liquids.
Analytical Procedure:
Place the pycnometer on the balance, then tare.
Fill the pycnometer with the oil.
Weigh the oil.
The API gravity is calculated according to the following formula:
141.5
API (degree) = -------------------------------------------------- - 131.5
Specific Gravity @ 60° F