Hypophosphoric Acid Formula – Structure, Properties, Uses, Sample Questions

Hypophosphoric acid is one of the chemical compounds and it has acidic nature with the formula of H₄P₂O₆, in which phosphorus is in an oxidation state. The Hypophosphoric acid consists of 4 Hydrogen, 2 Phosphorous, and 6 Oxygen atoms. and it consists of a P-P bond, for each phosphorous in the P-P bond contains 2 (P-OH) bonds and 1 (P-O) bond. The P-P bond length is 219 pm, the P-OH bond length is 159 pm and the P-O bond length is 151pm. One phosphorus atom consists of hydrogen and it is directly bonded to another Phosphorous atom. It is linked by an oxygen bridge to give phosphoric acid. Hypophosphoric acid is present as the dihydrate in the Solid state.

The Chemical formula of Hypophosphoric acid is H₄P₂O₆. It is generally existing as dihydrate H₄P₂O₆.2H₂O, another name is di-phosphoric acid.

Structure of Hypophosphoric Acid

The Hypophosphoric acid consists of 4 Hydrogen, 2 Phosphorous, and 6 Oxygen atoms. and it consists of a P-P bond, for each phosphorous in the P-P bond contains 2 (P-OH) bonds and 1 (P-O) bond. The P-P bond length is 219 pm, the P-OH bond length is 159 pm and the P-O bond length is 151pm.

Structure of Hypophosphoric Acid

Preparation of Hypophosphoric Acid

At room temperature, red phosphorous and sodium chlorite can be combined to make Hypophosphoric acid. When white phosphorous is partially dissolved in water, it oxidizes in the air, producing a mixture of Hypophosphoric acid, phosphorous acid, and phosphoric acid. 

2P + 4NaOCl₂ + 2H₂O  ⇢  H₄P₂O₆ + 2 NaCl

Properties of Hypophosphoric Acid

• Hypophosphoric acid is a white Solid in a dihydrate state and has no odour.
• The Melting point of Hypophosphoric acid is 54°C.
• Hypophosphoric acid is soluble in water.
• The molar mass of Hypophosphoric acid is 161.98 g/mol as a white crystalline powder.

Uses of Hypophosphoric Acid

Hypophosphoric acid has a wide range of applications. It can be used as a reducing agent as well as a bleaching agent. Aside from that, it’s a fantastic wetting agent. Not only that but it can also be used as a stimulant in pharmaceuticals as stimulant. And chemically it has wide applications like reducing agents, tetrabasic acid, and wetting agents. 

Health Effects 

Hypophosphoric acid is a highly corrosive substance. Chemical burns to the skin and eyes are possible. Furthermore, it may cause irritation in the upper respiratory system if inhaled. Not only that, but it has the potential to irritate the eye and eyelids. It is recommended that you remove it with water at all times. If not completed on time, it might cause long-term or irreversible vision impairment. In addition, prevent swallowing because it will harm the mucous lining of the mouth, as well as the throat, oesophagus, and stomach.

Sample Questions

Question 1: What is the chemical formula of Hypophosphoric acid and describe its structure?

Answer:

The chemical formula of Hypophosphoric acid is H₄P₂O₆. The Hypophosphoric acid consists of 4 Hydrogen, 2 Phosphorous, and 6 Oxygen atoms. and it consists of a P-P bond, for each phosphorous in the P-P bond contains 2 (P-OH) bonds and 1 (P-O) bond. The P-P bond length is 219 pm, the P-OH bond length is 159 pm and the P-O bond length is 151 pm.

Structure of Hypophosphoric Acid

Question 2: List down some known hypophosphate salts.

Answer:

Below listed are some known hypophosphate salts:

• K₄P₂O₆·8H₂O, 
• Ca₂P₂O₆·2H₂O, 
• K₃HP₂O₆·3H₂O, 
• K₂H₂P₂O₆·2H₂O, and
• KH₃P₂O₆ etc.

Question 3: What are some Health effects of the compound Hypophosphoric acid?

Answer:

Hypophosphoric acid is a highly corrosive substance. Chemical burns to the skin and eyes are possible. Furthermore, it may cause irritation in the upper respiratory system if inhaled. Not only that, but it has the potential to irritate the eye and eyelids. It is recommended that you remove it with water at all times. If not completed on time, it might cause long-term or irreversible vision impairment. In addition, prevent swallowing because it will harm the mucous lining of the mouth, as well as the throat, oesophagus, and stomach.

Question 4: What is the oxidation state of Phosphorus in H₄P₂O₆?

Answer:

The oxidation state of Phosphorus in H₄P₂O₆ is +4 only.

Question 5: Name one structural isomer of H₄P₂O₆.

Answer:

The structural isomer of H₄P₂O₆ is Isohypophosphoric acid.