Standard-state pressure = 100 000 Pa

Symbol
Value
100 000
Unit
Pa
Uncertainty
exact (by definition)
Copy-ready
100000

Exactly 1 bar — the thermodynamic reference pressure, and deliberately not the same thing as 1 atm.

NIST, Fundamental Physical Constants — Complete Listing (2022 CODATA adjustment), retrieved 2026-07-26.

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UsePhysics. "Standard-state pressure — 100 000 Pa." UsePhysics.com. https://usephysics.com/reference/standard-state-pressure. Value from the 2022 CODATA adjustment (NIST). Accessed [date].