Zinc

Blue-white metal used in galvanizing, electrochemistry, and hydrogen generation

Formula: Zn — Zinc, zincum
Appearance: Blue-white lustrous metal
Hazard: Low hazard (solid) · Fumes hazardous when melting

Properties

Moderately reactive metal. Density 7.13 g/cm³, melting point 419°C — low enough to cast easily. Dissolves in dilute acids with hydrogen evolution; also dissolves in concentrated NaOH (amphoteric behavior). Forms a protective zinc oxide layer in air. Used to galvanize steel (hot-dip or electroplated coating that sacrificially protects iron from corrosion). Available as granules, strips, or sheet.

Historical Context

Zinc was isolated in Europe by Andreas Sigismund Marggraf in 1746, though brass (zinc + copper) had been made for centuries without understanding zinc’s identity. The term “galvanizing” for zinc-coating steel honors Luigi Galvani, whose frog-leg experiments launched electrochemistry — zinc was one of the metals in Volta’s first battery.

Experiments

Hydrogen Generation: Drop zinc granules into dilute hydrochloric acid — vigorous hydrogen gas evolution. Collect the gas with a test tube and ignite for the characteristic “squeaky pop.” Demonstrates single displacement reactions and the activity series.

Galvanic Cell: Connect zinc and copper strips in copper sulfate solution. Measure the voltage (~1.1 V) with a multimeter — a simple demonstration of an electrochemical cell.

Experiments using this chemical:

Safety

Note

Solid zinc is safe to handle. Zinc oxide fumes from melting or burning zinc cause metal fume fever — ensure good ventilation. Zinc dust is flammable; handle carefully away from ignition sources.