Tankerman · Cargo Calculations — API to Specific Gravity
A crude oil is 40.0° API. Using SG (60/60°F) = 141.5 ÷ (131.5 + API), what is its specific gravity?
- A0.876
- B0.825✓ Correct
- C1.040
- D0.755
Explanation
SG = 141.5 ÷ (131.5 + 40.0) = 141.5 ÷ 171.5 = 0.825. Higher API gravity means a lighter (less dense) oil; 10° API corresponds to SG 1.000 (the density of water at 60°F).
Authority: API MPMS; ASTM-IP tables
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