VOLTAIC (GALVANIC) CELLS + ELECTROLYTIC CELLS

Which electrode is positive in a galvanic cell?

The cathode.

Which electrode increases mass?

The cathode (plating).

Direction of electron flow?

Anode → cathode.

Direction of anion flow (salt bridge)?

To the anode.

Direction of cation flow (salt bridge)?

To the cathode.

Why is the cathode positive?

Because reduction consumes electrons, lowering charge at that electrode.

Why does the anode shrink?

It loses atoms as they are oxidized into ions.

Why does a galvanic cell produce electricity spontaneously?

Because electrons naturally flow from the species with lower reduction potential to the one with higher reduction potential, lowering system energy.

Which electrode is positive in an electrolytic cell?

Anode

Direction of electron flow in electrolytic?

From battery’s negative terminal → cathode → solution → anode → battery’s positive.

Why do electrodes switch signs in electrolytic cells

The power source forces electrons against their spontaneous direction.

Why does electroplating require an electrolytic setup?

Because you must force reduction at an object that wouldn’t naturally be reduced by the ion solution.

Purpose of a salt bridge?

Maintain electrical neutrality.

Why must the salt bridge contain inert ions (NO₃⁻, Na⁺)?

They cannot react with electrode metals or ions.

Why must both positive and negative ions be present in the salt bridge?

To counteract BOTH positive charge buildup at the anode AND negative charge buildup at the cathode.

Do galvanic cells need a power source?

No — they are spontaneous and generate power.

Which cell type uses TWO beakers?

Galvanic

Which cell type uses ONE beaker?

Electrolytic

Do electrolytic cells need a salt bridge?

No — they use one beaker and a power source handles charge.

Which cell deposits (plates) metal on the cathode?

Electrolytic

What ions must the salt solution contain?

The SAME metal that is on the electrode (ex: Cu electrode → Cu²⁺ solution).

What is a salt solution in an electrochemical cell?

The solution that contains the ions of the metal electrode.

What parts does a galvanic cell need?q

Two electrodes, two ion solutions, a salt bridge, and wires.

Why two solutions in a galvanic cell?

Each electrode sits in its own metal-ion solution.

What parts does an electrolytic cell need?

Two electrodes, ONE solution, and a power source.