Tankerman · Cargo Calculations — Specific Gravity to API
A cargo has a specific gravity (60/60°F) of 0.850. What is its API gravity (API = 141.5 ÷ SG − 131.5)?
- A10.0° API
- B30.0° API
- C35.0° API✓ Correct
- D45.0° API
Explanation
API = (141.5 ÷ 0.850) − 131.5 = 166.47 − 131.5 = 34.97 ≈ 35.0° API. The API scale is an inverse measure of density referenced to water at 60°F.
Authority: API MPMS; ASTM-IP tables
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