Specific gravity (pycnometer) calculator

Inputs in the worked example

The live calculator starts with these values; change any of them and every result, check and diagram updates instantly.

Worked example — results

• ✓ Trials agree within 0.03 — Δ = 0.008
• ✓ Typical mineral soil range 2.55–2.85

Method, formulas and assumptions

• Gs,T = (m2 − m1) / [(m4 − m1) − (m3 − m2)]
• Gs,20 = Gs,T × ρw(T)/ρw(20 °C), ρw from the Tanaka (2001) water-density equation
• Report the mean of two trials; repeat if they differ by more than 0.03 (check the current AS 1289.3.5.1 limits)

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