Zinc nitrate, represented by the chemical formula Zn(NO₃)₂, is an inorganic compound with various industrial, laboratory, and agricultural applications. It consists of zinc (Zn²⁺) ions and nitrate (NO₃⁻) ions, making it a soluble salt that plays a role in different chemical processes.
This topic explores the name, structure, properties, preparation, uses, and safety considerations of zinc nitrate.
What is the Compound Name of Zn(NO₃)₂?
The IUPAC (International Union of Pure and Applied Chemistry) name of Zn(NO₃)₂ is Zinc Nitrate.
Alternative Names
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Zinc(II) Nitrate (indicating the +2 oxidation state of zinc)
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Dizinc Dinitrate (less commonly used)
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Zinc Nitrate Hexahydrate (Zn(NO₃)₂·6H₂O, the hydrated form)
Zinc nitrate is commonly found in its hexahydrate form, which means each formula unit is associated with six water molecules.
Chemical Structure and Formula
Molecular Formula
The molecular formula of zinc nitrate is:
Molecular Weight
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Anhydrous Zn(NO₃)₂: 189.36 g/mol
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Hexahydrate Zn(NO₃)₂·6H₂O: 297.49 g/mol
Chemical Composition
Zinc nitrate consists of:
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One zinc ion (Zn²⁺)
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Two nitrate ions (NO₃⁻)
Each nitrate ion contains one nitrogen (N) atom bonded to three oxygen (O) atoms, carrying a -1 charge. Since zinc has a +2 charge, two NO₃⁻ ions are needed to balance the charge.
Physical and Chemical Properties of Zn(NO₃)₂
| Property | Value |
|---|---|
| Chemical Formula | Zn(NO₃)₂ |
| Molar Mass | 189.36 g/mol (anhydrous) |
| Appearance | Colorless or white crystalline solid |
| Solubility in Water | Highly soluble |
| Melting Point | 110°C (decomposes) |
| Boiling Point | Decomposes before boiling |
| Density | 2.065 g/cm³ |
| Odor | Odorless |
Solubility and Dissociation in Water
Zinc nitrate is highly soluble in water, dissociating into Zn²⁺ and NO₃⁻ ions:
This makes it useful in applications where a soluble zinc source is needed.
Thermal Decomposition
When heated, zinc nitrate decomposes into zinc oxide (ZnO), nitrogen dioxide (NO₂), and oxygen (O₂):
This reaction produces toxic brown NO₂ fumes, which can be harmful in enclosed spaces.
How is Zinc Nitrate Prepared?
1. Reaction of Zinc with Nitric Acid
The most common way to produce Zn(NO₃)₂ is by reacting zinc metal with dilute nitric acid (HNO₃):
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Zinc nitrate solution is formed.
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Hydrogen gas (H₂) is released as a byproduct.
2. Reaction of Zinc Oxide with Nitric Acid
Another method involves zinc oxide (ZnO) reacting with nitric acid:
This reaction is commonly used in laboratories and industrial production.
3. Reaction of Zinc Carbonate with Nitric Acid
Zinc carbonate (ZnCO₃) also reacts with nitric acid to form zinc nitrate, water, and carbon dioxide:
This method is used when controlled CO₂ gas release is needed.
Applications of Zinc Nitrate
1. Agriculture and Fertilizers
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Used as a source of zinc nutrients for plants.
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Helps in correcting zinc deficiency in soil.
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Improves crop yield and growth.
2. Chemical Reagent in Laboratories
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Used in chemical synthesis and experiments.
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Involved in precipitation reactions to form zinc hydroxide or zinc oxide.
3. Explosives and Pyrotechnics
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Zinc nitrate is used in fireworks and explosives as an oxidizer.
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Enhances combustion reactions when mixed with other compounds.
4. Textile and Dyeing Industry
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Acts as a mordant (fixing agent) in fabric dyeing.
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Helps in color retention on textiles.
5. Medicine and Pharmaceuticals
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Used in antiseptic formulations.
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Plays a role in dermatological treatments.
6. Corrosion Inhibitors and Metal Coating
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Prevents metal rusting and corrosion.
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Used in galvanization and electroplating.
Safety Considerations and Handling of Zn(NO₃)₂
Health Hazards
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Irritation: Can cause skin and eye irritation.
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Inhalation: Fumes from decomposition can be toxic.
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Ingestion: Harmful if swallowed in large quantities.
Fire and Explosion Risks
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Acts as an oxidizer, which can intensify fires.
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Should be kept away from combustible materials.
Proper Storage and Disposal
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Store in a cool, dry, and well-ventilated area.
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Keep away from flammable substances.
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Dispose of according to environmental regulations.
Comparison with Other Zinc Compounds
| Compound | Formula | Solubility in Water | Uses |
|---|---|---|---|
| Zinc Nitrate | Zn(NO₃)₂ | Highly soluble | Fertilizers, pyrotechnics |
| Zinc Sulfate | ZnSO₄ | Soluble | Medicine, agriculture |
| Zinc Oxide | ZnO | Insoluble | Cosmetics, coatings |
| Zinc Hydroxide | Zn(OH)₂ | Insoluble | Chemical analysis, medicine |
| Zinc Carbonate | ZnCO₃ | Slightly soluble | Pharmaceuticals, pigments |
Zinc nitrate (Zn(NO₃)₂) is a versatile inorganic compound with wide applications in agriculture, industry, and chemistry. It is highly soluble in water, making it a valuable zinc source for fertilizers, pyrotechnics, and chemical processes.
Understanding its properties, preparation, and safety considerations ensures its effective and responsible use in different fields.
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