Zinc carbonate

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Zinc carbonate
Names
IUPAC name
Zinc carbonate
Other names
Smithsonite
Zinc monocarbonate
Zinc spar
Zincspar
Properties
ZnCO3
Molar mass 125.388 g/mol
Appearance White or multicolored (smithsonite)
Odor Odorless
Density 4.398 g/cm3 (20 °C)
Melting point 300 °C (572 °F; 573 K) (decomposes)
Boiling point Decomposes
0.001 g/100 ml (20 °C)
Solubility Reacts with acids
Insoluble in organic solvents
Vapor pressure ~0 mmHg
Hazards
Safety data sheet None
Flash point Non-flammable
Related compounds
Related compounds
Calcium carbonate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Zinc carbonate is a white, insoluble, zinc salt with chemical formula ZnCO3. With it, most simple zinc salts can be made by reaction with the corresponding proportions of sulfate.

Zinc carbonate occurs in nature as the mineral Smithsonite aka zinc spar.

Properties

Chemical properties

Zinc carbonate, like other carbonates, dissolves easily in acidic solution due to its basic nature, but is insoluble in water. This reaction gives off carbon dioxide. It will also dissolve in an excess of strong base to form zincates. Zinc carbonate can be thermally decomposed to form zinc oxide.

ZnCO3 → ZnO + CO2

Physical

Zinc carbonate is a white compound. The natural variety contains impurities, giving it blue, pink or green coloring. ZnCO3 has a density of 4.398 g/cm3. At high temperatures it will begin to decompose. Zinc carbonate is insoluble in water.

Availability

Zinc carbonate can be cheaply bought from chemical suppliers, or online.

Preparation

Zinc carbonate can be made by reacting zinc acetate or any other water soluble zinc(II) salt with sodium carbonate or sodium bicarbonate. It can also be made by the reaction of zincates with carbon dioxide. The resulting precipitate can then be filtered and dried, then stored in an environment free of acidic vapors.

Uses

  • Preparation of zinc salts and compounds
  • Make zinc oxide
  • Neutralize acids
  • White pigment

Handling

Safety

Zinc carbonate poses little toxicity to organisms and environment. Excess zinc may be harmful if ingested.

Storage

Zinc carbonate should be stored in closed containers, away from any acidic vapors.

Disposal

No special disposal is required. Zinc carbonate can be dumped in soil or trash, as long as it doesn't contain any heavy metals.

References

Relevant Sciencemadness threads