USNCO Exams Reference Page

Below is the standard information provided for reference in all USNCO exams. No additional information may be accessed while taking any USNCO exam.

Abbreviations and Symbols

Full Name Abbreviation/ Symbol
Amount Of Substance N
Ampere A
Atmosphere Atm
Atomic Mass Unit U
Avogadro Constant NA
Celsius Temperature °C
Centi– Prefix C
Coulomb C
Density D
Electromotive Force E
Energy Of Activation Ea
Enthalpy H
Entropy S
Equilibrium Constant K
Faraday Constant F
Free Energy G
Frequency Ν
Gas Constant R
Gram G
Hour H
Joule J
Kelvin K
Kilo– Prefix K
Liter L
Measure Of Pressure Mm Hg
Milli– Prefix M
Molal M
Molar M
Molar Mass M
Mole Mol
Planck’s Constant H
Pressure P
Rate Constant K
Reaction Quotient Q
Second S
Speed Of Light C
Temperature, K T
Time T
Vapor Pressure VP
Volt V
Volume V
Year Y


R = 8.314 J mol–1 K–1
R = 0.08314 L bar mol–1 K–1
F = 96,500 C mol–1
F = 96,500 J V–1 mol–1
NA = 6.022 x 1023 mol–1
h = 6.626 x 10–34 J s
c = 2.998 x 108 m s–1
0 °C = 273.15 K
1 atm = 1.013 bar = 760 mm Hg
Specific heat capacity of H2O = 4.184 J g–1 K–1


E = Eo(RT/nF) x lnQ

lnK = (—ΔHo/R) x (1/T) + constant

ln(k2/k1) = (Ea/R) x ((1/T1) — (1/T2))


Thank you to the Olympiad Examinations Task Force and the Olympiad Laboratory Practical Task Force. View all acknowledgements.