# 15 Facts on HCl + P2O5 What, How To Balance & FAQs

HCl is an acid and P2O5 is an oxide of phosphorous. Let us study the reaction HCl+P2O5.

HCl is a strong corrosive, colorless acid that reacts with P2O5, one of the oxides of phosphorous. P2O5 is a white solid without any specific smell.

Here, we will discuss all the vital aspects of the reaction between HCl and P2O5 in this article.

## What is the product of HCl and P2O5

The products of the reaction HCl + P2O5 are phosphorous oxychloride (POCl3) and metaphosphoric acid (HPO3). The reaction is as follows.

HCl + P2O5  =  POCl3 + HPO3

## What type of reaction is HCl + P2O5

This reaction HCl + P2O5 does not fall under any particular type of reaction.

## How to balance HCl + P2O5

The unbalanced equation for the reaction is

HCl + P2O5  =  POCl3 + HPO3

The following steps are followed to balance the equation-

• First, number of atoms- H, Cl, P, and O on both the reactant side and product side is checked.
• If the numbers are not same, we have to multiply the formulas of the compounds by the smallest figure as required in cases where it is not same.
• In the unbalanced equation, the number of P and H is the same on both sides.
• The number of Cl atoms on left hand side and right hand side is 1 and 3 respectively. So, we will multiply HCl by 3.
• 3HCl + P2O5  =  POCl3 + HPO3
• Now, the number of H atoms on left hand side and right hand side is 3 and 1 respectively. So, we will multiply HPO3 by 3.
• 3HCl + P2O5  =  POCl3 + 3HPO3
• Next, the number of O atoms on left hand side and right hand side is 5 and 10 respectively. So, we will multiply P2O5 by 2.
• The balanced equation is
• 3HCl + 2P2O5 =  POCl3 + 3HPO3

## HCl + P2O5 titration

The titration between HCl and P2O5 is not possible because it does not fulfill any category of titration methods due to their reaction between a strong acid and an oxide.

## HCl + P2O5 net ionic equation

An ionic equation for HCl + P2O5  reaction is not possible as, except for HCl, we cannot write the other three compounds as dissociated ions. P2O5, POCl3, and HPO3 are all covalent compounds.

## HCl + P2O5 conjugate pairs

HCl + P2O5  =  POCl3 + HPO3

• The conjugate base of HCl is Cl.
• Conjugate pair is not possible for P2O5 as it is not an acid or base.

## HCl + P2O5 intermolecular forces

• Dipole-dipole and London dispersion forces; are the two intermolecular forces in HCl. Among these, the first one is predominant in HCl.
• In P2O5, weak van der Waals forces are present.

## HCl + P2O5 reaction enthalpy

The value of reaction enthalpy for HCl + P2O5  reaction is -2341.5 kJ/mol.

## Is HCl + P2O5 a buffer solution

A buffer solution will not be formed by mixing HCl and P2O5. HCl being a strong acid cannot form a buffer solution.

## Is HCl + P2O5 a complete reaction

HCl + P2O5  is a complete reaction as the formation of the products POCl3 and HPO3, does not further react back to produce the reactants.

## Is HCl + P2O5 an exothermic or endothermic reaction

HCl + P2O5  reaction is exothermic as heat is liberated.

## Is HCl + P2O5 a redox reaction

HCl+P2O5 is not a redox reaction because in the molecules HCl, P2O5, HPO3, and POCl3 oxidation state does not change.

## Is HCl + P2O5 a precipitation reaction

HCl + P2O5  reaction is not an example of a precipitation reaction as the product POCl3 is liquid and HPO3 is a water soluble solid.

## Is HCl + P2O5 reversible or irreversible reaction

HCl + P2O5  reaction is an example of irreversible reaction as it proceeds in one direction only.

## Is HCl + P2O5  displacement reaction

HCl + P2O5  is not a displacement reaction as one part of the reactant is not replaced by another reactant.

#### Conclusion

In conclusion, when hydrochloric acid reacts with phosphorus pentoxide, the products are HPO3 and POCl3. HPO3, the soft, colorless solid, dissolves slowly in cold water and deliquesces in nature.