Answer: hydrogen
Step-by-step explanation:
"Standard electrode potential is the measure of the individual potential of reversible electrode at standard state with ions at effective concentration of 1 mol/dm³ and pressure of 1 atm."
Hydrogen is set as the arbitrary standard in comparison to other electrode potential because it has a set value of 0.00v
Standard electrode potential of
Oxygen (O2) = +0.40v
Hydrogen (H2) = 0.00v
Fluorine (F) = +2.87v
Lithium (Li) = -3.04v