Electrochemical Series Table

Interactive chart of Standard Electrode Potentials (E°). Build galvanic cells, calculate voltage, and predict reaction spontaneity instantly.

Cell Potential Calculator

Select two half-reactions from the table below to build a cell.

Anode (Oxidation)

Select a Reductant below

(Lower E° usually acts as Anode)

E°cell

Cathode (Reduction)

Select an Oxidant below

(Higher E° usually acts as Cathode)

Increasing Oxidizing Strength

Increasing Reducing Strength

2.87 V

F₂(g) + 2e⁻ ⇌ 2F⁻(aq)

Strong Oxidant

OxidantFluorine

ReductantFluoride

1.51 V

MnO₄⁻ + 8H⁺ + 5e⁻ ⇌ Mn²⁺ + 4H₂O

Strong Oxidant

OxidantPermanganate

ReductantManganese(II)

1.36 V

Cl₂(g) + 2e⁻ ⇌ 2Cl⁻(aq)

Strong Oxidant

OxidantChlorine

ReductantChloride

1.33 V

Cr₂O₇²⁻ + 14H⁺ + 6e⁻ ⇌ 2Cr³⁺ + 7H₂O

Strong Oxidant

OxidantDichromate

ReductantChromium(III)

1.23 V

O₂(g) + 4H⁺ + 4e⁻ ⇌ 2H₂O(l)

Strong Oxidant

OxidantOxygen

ReductantWater

1.07 V

Br₂(l) + 2e⁻ ⇌ 2Br⁻(aq)

Oxidant

OxidantBromine

ReductantBromide

0.80 V

Ag⁺(aq) + e⁻ ⇌ Ag(s)

Oxidant

OxidantSilver Ion

ReductantSilver

0.77 V

Fe³⁺(aq) + e⁻ ⇌ Fe²⁺(aq)

Oxidant

OxidantIron(III)

ReductantIron(II)

0.54 V

I₂(s) + 2e⁻ ⇌ 2I⁻(aq)

Oxidant

OxidantIodine

ReductantIodide

0.34 V

Cu²⁺(aq) + 2e⁻ ⇌ Cu(s)

Oxidant

OxidantCopper(II)

ReductantCopper

0.00 V

2H⁺(aq) + 2e⁻ ⇌ H₂(g)

Reference

OxidantHydrogen Ion

ReductantHydrogen

-0.13 V

Pb²⁺(aq) + 2e⁻ ⇌ Pb(s)

Reductant

OxidantLead(II)

ReductantLead

-0.25 V

Ni²⁺(aq) + 2e⁻ ⇌ Ni(s)

Reductant

OxidantNickel(II)

ReductantNickel

-0.44 V

Fe²⁺(aq) + 2e⁻ ⇌ Fe(s)

Reductant

OxidantIron(II)

ReductantIron

-0.76 V

Zn²⁺(aq) + 2e⁻ ⇌ Zn(s)

Strong Reductant

OxidantZinc Ion

ReductantZinc

-1.66 V

Al³⁺(aq) + 3e⁻ ⇌ Al(s)

Strong Reductant

OxidantAluminium Ion

ReductantAluminium

-2.37 V

Mg²⁺(aq) + 2e⁻ ⇌ Mg(s)

Strong Reductant

OxidantMagnesium Ion

ReductantMagnesium

-2.71 V

Na⁺(aq) + e⁻ ⇌ Na(s)

Strong Reductant

OxidantSodium Ion

ReductantSodium

-2.93 V

K⁺(aq) + e⁻ ⇌ K(s)

Strong Reductant

OxidantPotassium Ion

ReductantPotassium

-3.04 V

Li⁺(aq) + e⁻ ⇌ Li(s)

Strong Reductant

OxidantLithium Ion

ReductantLithium

Understanding Electrochemical Series

The Electrochemical Series (also known as the Activity Series) is a ranking of chemical elements and their ions based on their Standard Reduction Potential (E°). This value, measured in volts (V), quantifies the tendency of a species to gain electrons (undergo reduction) compared to the Standard Hydrogen Electrode.

Top of the Series (Positive E°)

Species with high positive E° values have a strong affinity for electrons. They serve as excellent Oxidizing Agents.

Strong Oxidizing Agents
Easily Reduced
Example: Fluorine (F₂)

Bottom of the Series (Negative E°)

Species with high negative E° values readily give up electrons. They serve as excellent Reducing Agents.

Strong Reducing Agents
Easily Oxidized
Example: Lithium (Li)

Scientific Deep Dive

The Power of Redox Reactions

Every battery involves a redox reaction. In a Galvanic Cell (Voltaic Cell), chemical energy is converted into electrical energy. The difference in potential between the cathode (reduction) and anode (oxidation) drives the flow of electrons through the circuit. The greater the difference in E°, the higher the voltage of the battery.

Predicting Spontaneity

To determine if a reaction will happen spontaneously, calculate the Standard Cell Potential (ΔE°_cell):

E°_cell = E°_cathode - E°_anode

If E°cell > 0 ➝ Spontaneous ✅If E°cell < 0 ➝ Non-Spontaneous ❌

How to Use the Calculator

Select Half-Cells

Click on any two rows in the table. The tool intelligently assigns one as Cathode and one as Anode.

Check Voltage

The tool automatically calculates the Cell Potential difference. Positive voltage means energy is released.

Analyze Spontaneity

Look for the green "Spontaneous" badge to confirm if the reaction is thermodynamically favorable.

Frequently Asked Questions

What is the Electrochemical Series?

The Electrochemical Series is a list of elements and their ions arranged in order of their standard electrode potentials (E°). It helps predict the tendency of species to gain or lose electrons.

What does a positive E° value mean?

A positive standard electrode potential (E°) indicates that the reduction reaction is spontaneous relative to the Standard Hydrogen Electrode (SHE). These species are strong oxidizing agents.

Which element is the strongest oxidizing agent?

Fluorine (F₂) is the strongest oxidizing agent with the highest positive E° value (+2.87 V), meaning it has the strongest tendency to gain electrons.

Which element is the strongest reducing agent?

Lithium (Li) is the strongest reducing agent with the most negative E° value (-3.04 V), meaning it has the strongest tendency to lose electrons.

How do I predict if a redox reaction will occur?

A redox reaction is spontaneous if the total standard cell potential (E°cell) is positive. Calculate this using E°cell = E°cathode (reduction) - E°anode (oxidation).

What is the Standard Hydrogen Electrode (SHE)?

The Standard Hydrogen Electrode (SHE) is the reference electrode against which all other potentials are measured. It is assigned a potential of exactly 0.00 V.

What happens if E°cell is negative?

If E°cell is negative, the reaction is non-spontaneous under standard conditions. It would require an external energy source (electrolysis) to proceed.

Does E° change with stoichiometry?

No. Standard electrode potential (E°) is an intensive property. Multiplying a half-reaction by a coefficient to balance electrons does NOT change the value of E°.

How does the Nernst Equation relate to this?

The Nernst Equation allows you to calculate the cell potential under non-standard conditions (concentrations other than 1 M). E = E° - (RT/nF)lnQ.

Why are noble metals at the top of the series?

Metals like Gold and Silver have high positive E° values, making them very difficult to oxidize (corrode). This stability is why they are called "noble" metals.