Electrochemistry

Silvery-grey liquid at the cathode and brown fumes at the anode.

Brown fumes at the cathode and a silvery-grey liquid at the anode.

Bubbles of colorless gas at the cathode and a solid grey deposit at the anode.

Greenish-yellow gas at the anode and bubbles of hydrogen at the cathode.

Solid sodium chloride

Liquid mercury

Aqueous glucose solution

Molten lead(II) bromide ($PbBr_{2}$)

To act as a catalyst to speed up the decomposition.

To lower the melting point of the electrolyte and improve conductivity.

To prevent the carbon anodes from reacting with oxygen.

To increase the density of the molten mixture so aluminum floats.

Component A (Positive Terminal)

Component B (Pure Metal Anode)

Component C (Object to be plated)

Component D (Electrolyte)

Aqueous copper(II) sulfate

Dilute sulfuric acid

Molten sodium chloride

Aqueous silver nitrate

To increase the electrical conductivity of the bumper.

To make the bumper lighter and more flexible.

To prevent corrosion and provide a decorative, shiny finish.

To allow the bumper to react more easily with oxygen.

They are much cheaper to manufacture.

Hydrogen is easier to extract from the air than oil.

They do not emit greenhouse gases at the point of use.

They rely on non-renewable fossil fuels to operate.

$2H_2 + O_2 \rightarrow 2H_2O$

$H_2 + O_2 \rightarrow H_2O_2$

$CH_4 + 2O_2 \rightarrow CO_2 + 2H_2O$

$2H_2O \rightarrow 2H_2 + O_2$

Oxygen

Hydrogen

Carbon monoxide

Nitrogen