Zinc Phosphate Formula – Structure, Properties, Uses, Sample Questions

Zinc Phosphate consists of the elements Zinc, Phosphorous, and Oxygen. Zinc is silvery-greyish brittle metal present in group-12 of the periodic table. It is the first element in group-12. Its atomic number is 30 and is represented by the symbol Zn. Zinc is one of the widely used metals. Phosphorus is a highly reactive nonmetal present in group-15 of the periodic table. Its atomic number is 15 and is represented by the symbol P. Oxygen is a highly reactive nonmetal present in the chalcogen group, i.e., group-16. Its atomic number is eight and is represented by the symbol O. 

Zinc Phosphate Formula 

Zinc Phosphate is an inorganic compound with the chemical formula Zn₃(PO₄)₂. Zinc Phosphate is widely used as a corrosion-resistant coating applied on metal surfaces which are put as primer pigment or as a part of electroplating. When compared to bare metal, the Zinc Phosphate coats better on a crystalline structure. So seeding agent such as sodium pyrophosphate is frequently used as a pre-treatment. The other names for Zinc Phosphate are Trizinc phosphate, Zinc orthophosphate, and Trizinc diphosphate. It is prepared by mixing powders of Magnesium oxide (MgO) and Zinc oxide (ZnO) consisting of a liquid principally of water, phosphoric acid, and buffers. The different forms of Zinc Phosphate are minerals such as hopeite, parahopeite, and tarbuttite. It originated from zinc phosphate cement.

Structure of Zinc Phosphate

Zinc Phosphate Structure

Physical Properties of Zinc Phosphate

• Zinc Phosphate appears in the form of white crystals.
• The molecular weight of Zinc Phosphate is 386.11 g/mol.
• The density of Zinc Phosphate is 3.998 g/cm³.
• The melting point of Zinc Phosphate is 900°C.
• It is a nonflammable compound.

Chemical Properties of Zinc Phosphate

• Zinc Phosphate is insoluble in water.
• It is known to be corrosion resistant. Therefore, the coating is applied on metal surfaces.

Uses of Zinc Phosphate

• Zinc Phosphate is used in the manufacturing of dyes.
• It is used as a plating agent as well as a surface treating agent.
• Zinc Phosphate is used as a corrosion inhibitor.
• It is used as an additive in paints.
• Zinc Phosphate is used in water treatment products.
• It is an anti-scaling agent.
• It is used in preparing rubber products.

Sample Questions

Question 1: What happens when Zinc Phosphate is eaten?

Answer:

When zinc phosphate is eaten, the acid present in the stomach makes it release the toxic gas phosphine. The phosphine in the stomach crosses into the body cells and stops the cells from energy production and even leads to die the cells. It mainly targets cells of lungs, liver and heart.

Question 2: Find the molar mass of Zinc Phosphate.

Answer:

Zinc Phosphate consists of 3 Zinc, 2 phosphorous and 8 oxygen atoms.

Atomic weight of Zinc element = 65.38

Atomic weight of Phosphorus = 30.973762

Atomic weight of each Oxygen = 15.999

Molecular weight of Zn₃(PO₄)₂ = (3 × 65.38) + (2 × 30.973762) + (8 × 15.999)

= 386.11

Question 3: What are the symptoms when exposed to Zinc Phosphate?

Answer:

The major symptoms include headache, breathing problems, vomiting and dizziness. When exposed to excessive quantities then it may cause problems like liver and kidney failure, coma and delirium.

Question 4: What happens to Zinc Phosphate when it is exposed to the environment?

Answer:

Any phosphine will breakdown when exposed to environment. So Zinc Phosphate will also breakdown when it exposed to water or moist soil. It breakdowns into phosphine or phosphoric acid when exposed to highly acidic conditions.

Question 5: How to prepare Zinc Phosphate?

Answer:

Zn₃(PO₄)₂ is prepared by mixing powders of Magnesium oxide (MgO) and Zinc oxide (ZnO) consisting of a liquid principally of water, phosphoric acid, and buffers.

Question 6: How Zinc Phosphate prevents corrosion?

Answer:

Zinc phosphate is used as corrosion resistant because it inhibit the anode process of metal corrosion and enhance the wet adhesion of the coating and prevent the horizontal diffusion of the corrosive medium into the metal interface and slow down the disbonding of Zinc phosphate coating.