# Conversion of Orthophosphoric acid to Pyro and Meta Phosphoric acid

• Chemistry
• Physics lover
In summary, the conversation discusses the existence of Pyrophosphoric and Metaphosphoric acid in solid form and the temperature required for their conversion to liquid state. The question does not specify the temperature of the final state, but only lists the temperature at which conversion takes place. The provided answer may be incorrect as the final temperature cannot be lower than the supplied temperature. It is suggested that the answer should be both solid, but further clarification is needed.

#### Physics lover

Homework Statement
Question pic is in My attempt.
Relevant Equations
Melting point of Pyrophosphoric acid
Melting point of Metaphosphoric acid

I know that both Pyro and Meta phosphoric acid exists in solid form.But the temperature mentioned here are more than melting points of both.
So the acids will be obtained in liquid state.But the answer was given as b).
I can't make out the reason.Please explain.

Physics lover said:
Homework Statement:: Question pic is in My attempt.
Relevant Equations:: Melting point of Pyrophosphoric acid
Melting point of Metaphosphoric acid

View attachment 260752

I know that both Pyro and Meta phosphoric acid exists in solid form.But the temperature mentioned here are more than melting points of both.
So the acids will be obtained in liquid state.But the answer was given as b).
I can't make out the reason.Please explain.

The question doesn't say anything about the temperature of the final state, it just lists temperature at which conversion takes place.

Borek said:
The question doesn't say anything about the temperature of the final state, it just lists temperature at which conversion takes place.
I cannot understand that.How can final temperature be lower than supplied temperature.Please explain a little bit.

You heat up the acid to convert it, you leave it to cool down, you report state of the product at the room temperature.

Borek said:
You heat up the acid to convert it, you leave it to cool down, you report state of the product at the room temperature.
Ok so the answer would be both solid?

## 1. What is the difference between orthophosphoric acid, pyrophosphoric acid, and metaphosphoric acid?

Orthophosphoric acid is the simplest form of phosphoric acid, with one phosphorus atom bonded to three oxygen atoms. Pyrophosphoric acid is a dimer of orthophosphoric acid, meaning it is made up of two orthophosphoric acid molecules bonded together. Metaphosphoric acid is a polymer of orthophosphoric acid, meaning it is made up of multiple orthophosphoric acid molecules bonded together in a chain.

## 2. How is orthophosphoric acid converted to pyrophosphoric acid?

Orthophosphoric acid can be converted to pyrophosphoric acid through a dehydration reaction, where water is removed from the orthophosphoric acid molecule to form the dimer, pyrophosphoric acid.

## 3. What is the purpose of converting orthophosphoric acid to pyrophosphoric acid?

Converting orthophosphoric acid to pyrophosphoric acid can be useful in industrial processes, such as in the production of detergents and fertilizers. Pyrophosphoric acid has different chemical properties than orthophosphoric acid, making it useful in different applications.

## 4. How is orthophosphoric acid converted to metaphosphoric acid?

Orthophosphoric acid can be converted to metaphosphoric acid through a condensation reaction, where multiple orthophosphoric acid molecules are bonded together to form a polymer chain. This reaction also involves the removal of water molecules.

## 5. What are the uses of metaphosphoric acid?

Metaphosphoric acid has various uses in the food industry, such as in the production of soft drinks and canned foods. It is also used as a preservative and flavor enhancer in food products. In addition, metaphosphoric acid is used in laboratory experiments and as a cleaning agent in the medical field.