月: 2023年1月

What Is Copper Sulfate?

Copper sulfate, consisting of monovalent copper (I) and divalent copper (II), is a significant chemical compound used for various applications. The chemical formula for copper (I) sulfate is Cu₂SO₄, while for copper (II) sulfate, it is CuSO₄. Typically, copper sulfate refers to the copper (II) form. Copper (I) sulfate appears as a colorless or gray powder, reacting readily with water and decomposing.

Copper (II) sulfate exists in both anhydrous and pentahydrate forms. The anhydrous form is white crystal that easily absorbs water to form the pentahydrate. The pentahydrate, naturally occurring as chalcanthite, is blue and is industrially produced by treating brass ore with air and water.

Uses of Copper Sulfate

Applications of copper sulfate include its use in the Bordeaux mixture, an agricultural fungicide made from copper sulfate and slaked lime. This solution is effective against bacterial and fungal diseases on fruit trees and vegetables. Additionally, copper sulfate is vital in infant formula to meet copper nutritional requirements, within standards set by regulatory authorities. It is also used in copper plating, as a catalyst, and in pigments.

Properties of Copper Sulfate

The anhydrous form is a white, water-soluble, hygroscopic powder that decomposes into copper oxide and sulfur trioxide at 650°C. The pentahydrate form, a blue crystal, dissolves in water, with its solubility varying with temperature.

The repeated information on the solubility of the pentahydrate form has been removed for conciseness.

Structure of Copper Sulfate

The structure of copper sulfate pentahydrate includes five molecules of water, with four directly coordinated to the copper ion. The sulfate ion is weakly coordinated, and the crystal structure allows for hydrogen bonding among water molecules and sulfate ions. Heating the pentahydrate leads to sequential water loss, altering the crystal structure and coordination.

Other Information on Copper Sulfate

1. Copper Sulfate Production Method

Copper sulfate pentahydrate is produced industrially by dissolving copper compounds in sulfuric acid and evaporating the solution. Anhydrous copper sulfate is made by dehydrating the pentahydrate, with careful temperature control to prevent decomposition into other compounds.

• Dehydration: CuSO₄・5H₂O → CuSO₄・3H₂O → CuSO₄・H₂O → CuSO₄
• Decomposition: CuSO₄ → CuO + SO₂ + O₂

2. Safety Information on Copper Sulfate

Copper sulfate poses significant health risks, including acute toxicity through inhalation or ingestion. Symptoms of copper sulfate poisoning can include gastrointestinal distress, hemolytic anemia, and potential damage to the liver and kidneys.

What Is Silver Sulfate?

Silver(I) sulfate is a monovalent silver sulfate with the composition Ag₂SO₄.

The CAS number is 10294-26-5. It is often referred to as silver sulfate (I) sulfate, with the valence number indicated. Silver sulfate is classified as a deleterious substance under the Poisonous and Deleterious Substances Control Law.

Although nonflammable, it can produce irritating or toxic fumes when heated to high temperatures. Theoretically, silver(II) sulfate also exists, but in reality, it is almost nonexistent, and silver sulfate refers to silver(I) sulfate.

Uses of Silver Sulfate

The main uses of silver sulfate are in silver plating materials, synthetic reagents (a source of silver), catalysts, photography, antibacterial materials, hair dyes, and colorants. Silver plating is usually done using silver cyanide, but silver sulfate is attracting attention as a silver plating method that does not use highly toxic cyanide. It is also used in household and medical products, as it is considered the least allergenic of all metals.

1. Wound Dressing and Dye

Due to its antibacterial properties, silver is used in wound dressings and antibacterial products, and is also used in hair coloring agents due to its tendency to turn black under light.

2. Chemical Analysis

A typical use of silver sulfate as a reaction catalyst is in the sulfonation of polystyrene. Silver sulfate is also used in chemical analysis for chemical oxygen demand (COD).

Silver sulfate reacts with chlorine to form silver chloride, so the addition of silver sulfate during COD analysis removes chlorine ions that would otherwise interfere with the measurement. This allows for a catalytic effect that accelerates the reaction.

Properties of Silver Sulfate

Silver sulfate has a molecular weight of 311.799, a melting point of 652°C, a boiling point of 1,085°C (decomposition), and a white or colorless, crystalline or crystalline powder in appearance at room temperature. Its density is 5.45 g/mL. It is soluble in nitric acid, sulfuric acid, and aqueous ammonia, but insoluble in water (solubility in water: 0.796g/100mL).

The crystals are colorless orthorhombic crystals with a face-centered cubic lattice structure.

Types of Silver Sulfate

Silver sulfate is commonly sold as a precious metal chemical product, industrial chemical product, and reagent product for research and development.

1. Precious Metal Chemicals

As a precious metal chemical product, it is sold in units such as 500 g bottles, 5 kg bags, or polyethylene bottles. The main intended applications are reagents, catalysts, colorants, and materials for silver plating.

2. Reagent Products for Research and Development

R&D reagent products are available in 25g, 100g, 500g, and other capacities. In addition to pure substances, they are sometimes sold as sulfuric acid solutions. These reagent products can usually be stored at room temperature.

Other Information on Silver Sulfate

1. Synthesis of Silver Sulfate

Silver sulfate is obtained as a crystalline precipitate by dissolving silver in hot concentrated sulfuric acid and diluting it with water. The byproducts of this reaction are sulfur dioxide and water.

In other methods, crystals are precipitated by adding dilute sulfuric acid or aqueous sulfate solution to an aqueous silver(I) nitrate solution. This method, called aqueous precipitation, is also used in commercial production. Silver(I) sulfide can also be synthesized by calcination of silver(I) sulfide in air at 1085°C or lower.

2. Dissolution of Silver Sulfate

Silver sulfate turns black when decomposed by light. However, it is regarded as a stable substance when stored or handled normally.

In sulfuric acid or nitric acid, silver sulfate forms hydrogen sulfate, and in ammonia water, silver sulfate dissolves by forming an amine complex. The reaction with sulfuric acid is reversible, and silver hydrogen sulfate reverts to silver sulfate through hydrolysis.

3. Regulatory Information on Silver Sulfate

Silver sulfate is designated as a deleterious substance under the Poisonous and Deleterious Substances Control Law. When handling silver sulfate, must be handled properly in compliance with laws and regulations.

What Is Zinc Sulfate?

Figure 1. Structure of Zinc Sulfate

Zinc sulfate is an inorganic compound formed by the reaction of zinc sulfate and zinc.

Its chemical formula is ZnSO₄. When crystallized from aqueous solution, it can form 1, 6, or 7 hydrates, depending on temperature.

Zinc sulfate powder is irritating to the eyes and is designated as a deleterious substance under the Poisonous and Deleterious Substances Control Law, and heating may produce toxic fumes and vapors. Mixing or contact with alkaline substances should be avoided in the case of zinc sulfate solutions.

Uses of Zinc Sulfate

Zinc sulfate is widely used as one of the raw materials for pharmaceutical, agricultural, and industrial products.

In pharmaceuticals, the astringent and antiseptic properties of zinc sulfate are used to make eye drops for the treatment of conjunctivitis and blepharitis. For industrial use, it is used to coagulate liquid rayon in the rayon manufacturing process and is also available as a wood preservative and paper bleaching agent. In agriculture, it is added to feed to strengthen the mineral content and mixed into Bordeaux solution, an agricultural fungicide, to prevent damage to crops.

Zinc sulfate can also be used as a food additive under certain conditions. It is added to animal feed as an essential zinc source, containing up to several hundred mg per kilogram of feed. It is considered safe in trace amounts. However, an overdose of 2-8 mg per kg of body weight can cause stomach discomfort with nausea and vomiting.

Properties of Zinc Sulfate

Zinc sulfate monohydrate is a colorless powder with a specific gravity of 3.28 at 15°C. Zinc hexahydrate is a colorless monoclinic crystal with a specific gravity of 2.072 at 15°C. Dihydrate and tetrahydrate are also known.

The heptahydrate is a colorless, odorless crystal with astringent properties. It air-dissolves in air and dissolves in crystalline water at about 50°C when heated rapidly. On gentle heating, it becomes hexahydrate at 39°C, monohydrate at 70°C, and anhydrate at 240-280°C. Heptahydrate is soluble in water and virtually insoluble in ethanol. Aqueous solutions are weakly acidic due to hydrolysis.

The anhydrate of zinc sulfate decomposes to Zn₃O(SO₄)₂ at 600°C and to zinc oxide (ZnO) at 930°C.

Structure of Zinc Sulfate

Figure 2. Zinc Sulfate in Aqueous Solution

Zinc sulfate is formed when zinc-containing materials are treated with zinc sulfate. Pharmaceutical-grade zinc sulfate can be synthesized by treating high-purity zinc oxide with zinc sulfate.

In an aqueous solution, the hydrate of zinc sulfate is composed entirely of [Zn(H₂O)₆]²⁺ and SO₄^2-. This coordination compound has only water as a ligand and contains zinc ions. When this solution is treated with a solution containing barium ions, barium sulfate is formed.

Other Information About Zinc Sulfate

1. Natural Zinc Sulfate

ZnSO₄・7H₂O occurs as the mineral goslarite. (Zn, Cu, Fe)SO₄-7H₂O is found as a trace mineral in zinc melanterite. Low hydrates of zinc sulfate such as (Zn, Fe)SO₄・6H₂O (Bianchiite), (Zn, Mg)SO₄・4H₂O (Boyleite), and (Zn, Mn)SO₄・H₂O (Gunningite) are not commonly found in nature.

2. Related Compounds of Zinc Sulfate

Figure 3. Related Compounds of Zinc Sulfate

Zinc sulfate 7-hydrate is orthorhombic and has the same structure as ferrous sulfate 7-hydrate and Magnesium Sulfate 7-hydrate. a = 11.779Å, b = 12.050Å, c = 6.822Å. 6 H₂O molecules are coordinated to Zinc Sulfate, and 1 H₂O molecules are coordinated to the oxygen of the sulfate ion.

Most metal aqua complexes are mononuclear. The general formula is [M(H₂O)₆]ⁿ⁺ (n = 2, 3), forming an octahedral structure. Examples are [Cu(H₂O)₆]²⁺、 [Ni(H₂O)₆]²⁺、 [Co(H₂O)₆]²⁺、 [Mn(H₂O)₆]²⁺. Water molecules function as Lewis bases, donating electron pairs to metal ions.

What Is Manganese Sulfate?

Manganese sulfate is the sulfate of manganese.

There are two types of manganese sulfate, manganese sulfate(II) and manganese sulfate(III), depending on the oxidation number of manganese. Like most metal sulfates, manganese sulfate(II) can be anhydrous or hydrate, with 1, 4, 5, and 7 hydrates known.

Manganese sulfate(II) is nonflammable. However, it decomposes on heating, producing toxic gases containing sulfur oxides. Ingestion can affect the central nervous system and may cause hereditary diseases.

Uses of Manganese Sulfate

Manganese sulfate is widely used as a raw material for products in the industrial and agricultural fields.

In industry, it is used as a raw material for manganese metal and manganese compounds. It is used as a raw material for desiccants in paints or printing inks, as a rust inhibitor to prevent rusting of metals, and as a pigment for ceramics (a coloring agent for ceramic products).

In the agricultural field, manganese is one of the trace elements necessary for plant growth. Manganese sulfate is added to fertilizers to promote plant photosynthesis and aid in plant growth.

Properties of Manganese Sulfate

Manganese sulfate(II) has a light red color and is a crystalline or crystalline powder solid. It is soluble in water and virtually insoluble in ethanol. It is deliquescent, with a melting point of 700°C, and decomposes at 850°C.

Depending on the temperature, manganese sulfate(II) gives various hydrates: anhydrous when heated above 280°C; anhydrous is white and lumpy; below 9°C, 7-hydrate is formed; between 9 and 26°C, 5-hydrate is formed; between 26 and 27°C, orthorhombic 4-hydrate is formed; and above 27°C, 1-hydrate is formed. Common commercial products are tetrahydrate.

Oxidation of manganese sulfate(II) with potassium permanganate produces manganese dioxide, which is used in dry cell materials.

Structure of Manganese Sulfate

The chemical formula for manganese sulfate(II) is MnSO₄. The molar mass is 151.001 g/mol for the anhydride, 169.02 g/mol for the monohydrate, and 223.07 g/mol for the tetrahydrate. The density is 3.25 g/cm³ for anhydride, 2.95 g/cm³ for monohydrate, and 2.107 g/cm³ for tetrahydrate. The crystal structure of anhydride is orthorhombic, while that of monohydrate and tetrahydrate are monoclinic.

Other Information on Manganese Sulfate

1. Natural Manganese Sulfate(II)

Manganese sulfate(II) is an important precursor to manganese metal and various manganese compounds. It occurs naturally as monohydrate in Szmikite, tetrahydrate in Ilesite, pentahydrate in Jokokuite, and septahydrate in Mallardite.

2. Synthesis of Manganese Sulfate(II)

When sulfuric acid reacts with manganese metal, hydrogen is generated and manganese Sulfate(II) is formed. Manganese ore is usually purified by treating it with sulfuric acid to produce an aqueous manganese sulfate solution.

Manganese sulfate(II) can also be synthesized from sulfuric acid and manganese hydroxide with water. In the laboratory, it can also be obtained by the reaction of sulfur dioxide and manganese dioxide.

Manganese sulfate(II) also occurs as a by-product of industrial processes such as the production of hydroquinone and anisaldehyde using manganese dioxide as the oxidizing agent.

3. Characteristics of Manganese Sulfate(III)

The chemical formula of manganese sulfate(III) is Mn₂(SO₄)₃. It is a dark green powder with a molecular weight of 398.07 g/mol and a density of 3.24 g/cm³.

Manganese sulfate(III) can be obtained by dissolving manganese(IV) oxide monohydrate or potassium permanganate in concentrated sulfuric acid, or by heating Mn₂(SO₄)₃･H₂SO₄･H₂O. When dissolved in water, it becomes a red solution, and Mn(OH)₃ is precipitated by hydrolysis.

What Is Magnesium Sulfate?

Magnesium sulfate is a white crystalline to crystalline powdered metal salt.

It is also known as Epsom salt or Epsom salt, especially in its heptahydrate form.

Uses of Magnesium Sulfate

Magnesium sulfate is widely used as a highly safe chemical.

1. Fertilizer

In pesticide applications, magnesium sulfate monohydrate is mainly used. Chlorophyll, which plants need for photosynthesis, contains magnesium sulfate, so magnesium sulfate can be mixed into fertilizers to aid plant growth.

The advantage of magnesium sulfate is that it is more soluble than other magnesium soil amendments. In addition, the pH of its aqueous solution is nearly neutral, so it does not significantly affect soil pH when applied.

2. Bathing Agent

In Europe and the United States, magnesium sulfate has long been used as a bathing agent. It is expected to have a warming effect and relieve pain.

3. Laxatives and Enemas

Magnesium sulfate is a fast-acting salt laxative. It has long been used for medicinal purposes and suppresses the absorption of water in the intestines. It also concentrates water in the intestines and softens stools to promote defecation.

Magnesium poisoning is one of the serious side effects of Magnesium sulfate. Symptoms include lethargy, muscle weakness, breathlessness, drowsiness, fever, and hypotension. When taking large doses, be aware of the above symptoms.

4. Organic Synthetic Chemistry

Magnesium sulfate is used as a drying agent in organic chemical synthesis experiments due to its high affinity for water. It can be added to the organic solvent phase during post-reaction post-treatment to remove water. Inorganic sulfates such as Sodium Sulfate and Calcium Sulfate can be used in the same way.

5. Other

Magnesium sulfate is one of the components found in seawater. It is also found in small amounts in bittern, which coagulates tofu.

It is also used as a pharmaceutical, food additive, and feed additive to treat hypomagnesemia, arrhythmia, and eclampsia.

Properties of Magnesium Sulfate

The chemical formula of the anhydride is represented by MgSO₄, with a molecular weight of 120.37. The CAS number is registered as 7487-88-9.

Its melting point is 1,124°C and it decomposes upon melting. An odorless compound with hygroscopic properties, it is soluble in water, insoluble in ethanol, and practically insoluble in acetone and diethyl ether. It reacts with water and releases heat.

Its pH, which indicates the degree of acidity or alkalinity, ranges from 5.0 to 8.0 (50 g/L, 25°C).

Types of Magnesium Sulfate

Because anhydrous magnesium sulfate is unstable, it is usually found in nature as a hydrate. Known hydrates include 1 to 11 water molecules bound to 1 magnesium sulfate.

In nature, 7-hydrate is the most common. The CAS number for the septahydrate is 10034-99-8. 7-hydrate can be heated to monohydrate at 120°C and anhydrous at 250°C. The anhydrous form is called epsomite.

Other Information on Magnesium Sulfate

1. Production Method of Magnesium Sulfate

Magnesium sulfate can be obtained directly from natural resources. Magnesium sulfate can also be synthesized by reacting sulfuric acid with magnesium oxide or magnesium carbonate.

2. Handling and Storage Precautions

Precautions for Handling
Use in a location with a local exhaust ventilation system. Wear personal protective equipment when using.

In Case of Fire
Thermal decomposition may release irritating and toxic gases and vapors. Use a fire extinguisher suitable for the surrounding environment.

In Case of Skin Contact
Wear protective clothing and protective gloves to prevent skin contact. If skin contact occurs, immediately wash off with large amounts of water and soap. If symptoms persist, contact a physician.

In the Case of Eye Contact
Always wear protective glasses or goggles when using the product. In the unlikely event of eye contact, remove contact lenses and rinse cautiously with water for several minutes. Seek immediate medical attention.

For Storage
Keep sealed in a polyethylene or polypropylene container. Store locked in a cool, well-ventilated place out of direct sunlight.

What Is Barium Sulfate?

Barium sulfate, with a molecular weight of 233.39 and a chemical formula of BaSO4, is formed by reacting sulfuric acid with barium metal or its compounds. It appears as a white or transparent crystalline powder and is practically insoluble in water, ethanol, and diethyl ether, as well as hydrochloric and nitric acids.

Barium sulfate is non-flammable but decomposes at temperatures above 1600°C, releasing toxic sulfur oxide vapors. While generally safe for human use, some individuals may experience allergic reactions to it.

Uses of Barium Sulfate

This chemically stable compound finds widespread use in medical and industrial applications due to its excellent light and heat resistance. Industrially, it’s used in electronic materials, coatings, white plastics, acrylic resin, glass, and sometimes in cosmetics. In medical settings, barium sulfate is used as a contrast agent for X-ray imaging of the digestive tract.

Use in X-Ray Diagnosis (Double Contrast Method)

For X-ray diagnostics, a suspension of barium sulfate is prepared and used in conjunction with air or carbon dioxide gas to enhance contrast and visualize minute mucosal irregularities. Care is taken to maintain the concentration of the suspension and prevent rapid gastric expansion. Post-examination, prompt elimination of barium sulfate is essential, requiring adequate fluid intake, and in cases of persistent gastrointestinal symptoms, further examination and appropriate measures are necessary.

What Is Nickel Sulfate?

Nickel(II) sulfate is a sulfate of sulfuric acid with the composition NiSO₄.

Nickel(II) sulfate is generally used to indicate the valence. In addition to anhydride, mono-, di-, tetra-, hexa-, and heptahydrate are also known.

CAS registration numbers are 7786-81-4 for anhydrous, 10101-97-0 for hexahydrate, and 10101-98-1 for heptahydrate.

Uses of Nickel Sulfate

Nickel sulfate is mainly used for electrolytic nickel plating, electroless nickel plating, nickel catalysts in general, catalytic agents, black colorants for zinc and brass, paints and varnishes, pigments for ceramics, catalysts in general, and aluminum-colored batteries.

Nickel sulfate is used as one of the materials for plating metals and surface treatments such as plastics because of its corrosion and wear resistance. Plating or surface treatment with nickel sulfate not only improves durability and wear resistance but can also alter technical or physical properties such as electrical conductivity.

In battery applications, nickel is also used for cathodes and in a variety of products in industries such as automobiles, aircraft, and electronics.

Properties of Nickel Sulfate

1. Basic Information on Nickel Sulfate (Anhydride)

Nickel sulfate anhydride has a molecular weight of 154.75, a melting point of over 100°C, a boiling point of 840°C, and a yellow solid appearance at room temperature. It has a density of 3.68 g/mL and is readily soluble in water, with aqueous solutions showing acidity (solubility: 650 g/L (20°C)). It is insoluble in organic solvents such as ethanol, ether, and acetone.

2. Basic Information on Nickel Sulfate (Hexahydrate)

Nickel sulfate hexahydrate NiSO₄・6H₂O has a molecular weight of 262.836, a melting point of 53°C, a boiling point of 100°C (decomposition), and a green crystal appearance at room temperature. It is readily soluble in ethanol and ammonia and is known to dissolve in water at 50°C. Its density is 2.07 g/mL.

Types of Nickel Sulfate

Nickel sulfate is mainly sold as an industrial metal or industrial nickel compound and as a reagent product for research and development.

1. Industrial Products

For industrial use, crystals are sold in 20 kg bags and other capacities, and solution products exist in concentrations such as 35% and 30%. Solution products are mainly supplied for replenishing the nickel component of watt baths.

Crystal products are used for nickel plating, including electroplating and electroless plating, and are also envisioned for applications other than plating, such as aluminum coloration, catalysts, and battery materials. Due to its many applications, the substance is sold by a variety of companies.

2. Reagent Products for Research and Development

Reagent products for research and development are available in 25g, 100g, 500g, and other capacities. Possible applications include nickel ion sources for analysis, raw materials for plating, and catalyst raw materials.

In addition to pure substances, some manufacturers sell 0.5 mol/L solutions as a standard solution for volumetric analysis. The substance is usually handled as a reagent product that can be stored at room temperature.

Other Information on Nickel Sulfate

1. Synthesis of Nickel Sulfate

Nickel sulfate is synthesized by the reaction of nickel sulfate with metallic nickel. Nickel(II) oxide, nickel(II) hydroxide, or nickel carbonate can be used instead of metallic nickel. Hydrogen is a byproduct of this reaction.

Nickel sulfate can also be obtained by the reaction of nickel sulfate and nickel oxide or nickel sulfate and nickel hydroxide (the byproduct is water).

2. Reactivity of Nickel Sulfate

Nickel sulfate is a nonflammable substance that decomposes when heated to form toxic sulfur trioxide and nickel(II) oxide.

Nickel sulfate weathers in air to a white powder, but returns to a green color when water is added. The hydrate loses four molecules at 100°C, six molecules at 103.3°C, and all water at 279.4°C.

What Is Sodium Sulfate?

Sodium sulfate is a salt of sodium sulfate and sodium hydroxide with the chemical formula Na₂SO₄.

It is also called glauber’s salt. When distinguishing it from the anhydrous salt (Na₂SO₄・10H₂O), Na₂SO₄ is called anhydrous glauber’s salt, while the anhydrous salt is called crystalline glauber’s salt.

Uses of Sodium Sulfate

Sodium sulfate is widely used as a food additive, pharmaceutical, reagent, and for industrial purposes because it is nonflammable and has almost no harmful effects on the human body. For industrial use, it is used as one of the raw materials for manufacturing glass and pulp, and as a raw material for producing sodium sulfide. Its high hygroscopicity can also be used as a desiccant.

For household products, it is used as an auxiliary agent (builder) to improve the cleaning power of neutral detergents, and as a raw material for bath salts. Other uses include mining and smelting, dyeing, dye intermediates, pharmaceuticals, and the manufacture of precipitable barium sulfate.

Properties of Sodium Sulfate

Sodium sulfate comes in two forms: decahydrate (Na₂SO₄・10H₂O) and anhydrate (Na₂SO₄₎, both of which are hydrous salts.

1. Crystalline Glauber’s Salt (Na₂SO₄・10H₂O)

Molecular weight is 322.21 and specific gravity is 1.46. It is well soluble in water, and at 32.4℃, it changes from decahydrate to anhydrous. its solubility in water increases with increasing temperature up to 32.4℃, but above 32.4℃, solubility decreases with increasing temperature.

It is soluble in glycerin, insoluble in alcohols, and fats soluble.

2. Anhydrous Glauber’s Salt (Na₂SO₄)

Molecular weight is 142.04 and specific gravity is 2.698. Its melting point is 884°C. It is soluble in glycerin and insoluble in alcohols. It appears as a colorless or white, crystalline or crystalline powder solid.

It is characterized by high hygroscopicity and mixing or contact with aluminum and magnesium should be avoided.

Other Information on Sodium Sulfate

How Sodium Sulfate Is Produced

Sodium sulfate is produced directly from nature. It is produced in the United States and China as crystalline glauber’s salt and condensed salt (a mixture of sodium sulfate and calcium sulfate).

In industry, sodium sulfate is generally produced by refining low-purity sodium sulfate, a byproduct of the manufacture of rayon and other industrial products, to produce high-purity sodium sodium sulfate. The raw materials used are glauber’s salt, which is a byproduct of rayon production, and glauber’s salt byproduct, which is a byproduct of other industrial products.

When using glauber’s salt, soda ash is added to glauber’s salt to neutralize excess sulfuric acid, which is then heated and concentrated to precipitate sodium sulfate. This is further dehydrated, dried, and pulverized to refine the sodium sulfate.

1. Rayon
Cellulose + NaOH → Viscose
Viscose + H₂SO₄ → Viscose rayon + Na₂SO₄

Cellulose is dissolved in sodium hydroxide to make viscose. Viscose rayon is produced by precipitating the viscose solution in dilute sulfuric acid in fibrous form. Sodium sulfate is produced during this neutralization reaction. The residue after the fibers are recovered is rayon glauber’s salt.

2. Production of Sodium Dichromate
2Na₂CrO₄ + H₂SO₄ → Na₂Cr₂O₇ + Na₂SO₄ + H2O

3. Production of Ammonium Perchlorate
(NH₄)₂SO₄ + 2NaClO₄ → 2NH₄ClO₄ + Na₂SO₄

4. Production of Boric Acid
Na₂B₄O₇ + H₂SO₄ + 5H₂O → 4H₃BO₃ +Na₂SO₄

5. Production of Formic Acid
2HCOONa + H₂SO₄ → 2HCOOH + Na₂SO₄

What Is Cobalt Sulfate?

Cobalt sulfate, represented as CoSO₄, includes anhydrous, monohydrate, and heptahydrate forms of cobalt(II) sulfate and is recognized for its dark red crystals. It is classified under various safety regulations due to its harmful effects on human health.

Uses of Cobalt Sulfate

Used in cobalt plating, magnetic materials, ceramic glazes, and as a precursor for other cobalt salts, cobalt(II) sulfate’s applications span across several industries. It’s also utilized in pharmaceuticals as a mineral ingredient in anemia drugs and as a feed additive in agriculture. Cobalt(III) sulfate serves as a potent oxidizing agent.

Properties of Cobalt Sulfate

1. Cobalt Sulfate (II)

With melting points of 735°C for anhydrous CoSO₄ and 74°C for its heptahydrate, cobalt(II) sulfate transitions to anhydride upon heating. It is soluble in water, methanol, and ethanol.

2. Cobalt Sulfate (III)

Cobalt(III) sulfate demonstrates strong oxidizing capabilities, able to oxidize substances from ethanol to acetaldehyde and hydrochloric acid to chlorine.

Structure of Cobalt Sulfate

1. Cobalt Sulfate (II)

Cobalt(II) sulfate forms reddish crystals in anhydrous and monohydrate forms, with the heptahydrate forming dark red columnar crystals. The densities vary across its forms, with the anhydrous version being the densest.

2. Cobalt Sulfate (III)

The octahydrate form of cobalt(III) sulfate appears as blue, needle-like crystals, indicating its distinct chemical and physical properties.

Other Information on Cobalt Sulfate

1. Production of Cobalt Sulfate

Naturally occurring as beaverite, cobalt(II) sulfate heptahydrate is synthesized by dissolving cobalt oxide in sulfuric acid. Cobalt(III) Sulfate is produced at lower temperatures through electrolysis of an acidic cobalt(II) sulfate solution.

2. Synthesis of Cobalt Sulfate

For cobalt(II) sulfate heptahydrate, synthesis involves the precipitation of cobalt oxide in sulfuric acid at temperatures below 41.5°C. Cobalt(III) sulfate, decomposing at 35°C but soluble in sulfuric acid without decomposition, is synthesized by low-temperature electrolysis of a cobalt(II) sulfate solution. Hydrolysis of cobalt(III) sulfate can produce oxygen and convert back to cobalt(II) sulfate.

3. Hazards of Cobalt Sulfate

Exposure to cobalt(II) sulfate has been linked to toxic and carcinogenic effects, with historical incidents highlighting the dangers of improper handling. It decomposes upon heating, emitting toxic sulfur oxides. Cobalt sulfate poisoning in Quebec, Canada, resulted in multiple fatalities, underscoring the need for stringent safety measures.

4. Regulatory Information

Cobalt sulfate is regulated under various safety and health laws due to its hazardous nature. It is essential to adhere to guidelines for handling, storage, and disposal to minimize environmental impact and health risks. Proper labeling and notification are required under the Industrial Safety and Health Law.

5. Environmental Impact

Due to its toxicity, cobalt sulfate poses potential risks to aquatic life and the environment. Its use in industrial and agricultural applications necessitates careful management and adherence to environmental regulations to prevent contamination.

What Is Chromium Sulfate?

Chromium sulfate, represented by the chemical formula Cr₂(SO₄)₃ for the anhydride and various hydrate forms, is an important compound in industrial applications such as tanning, dyeing, and chrome plating. With its toxic and corrosive nature, safe handling and disposal practices are crucial.

Uses of Chromium Sulfate

Primarily used in the tanning industry to improve the quality of leather, chromium sulfate also finds applications in dye production, electrolytic polishing, and as a mordant. Its role extends to the production of catalysts, antiseptic agents, and metal allergy testing.

Properties of Chromium Sulfate

This compound is a purple or red solid, soluble in water, and presenting acidic solutions. It remains stable under general conditions but acts as an oxidizing agent and catalyst in various chemical reactions.

Structure and Types of Chromium Sulfate

Chromium sulfate exists primarily in two oxidation states: Chromium(II) sulfate, which is highly oxidizable and serves as an analytical reagent, and chromium(III) sulfate, used in broader industrial applications. Each form exists in several hydrated states, indicating its versatile nature in reacting and forming compounds.

Other Information on Chromium Sulfate

Safety and Regulations

Due to its toxicity, chromium sulfate is regulated under various laws, emphasizing the importance of safety measures in its handling. It’s classified as a carcinogenic substance and requires specific labeling and notification under industrial safety regulations.