Question

Classify the following reaction : PCl5(s) + H2O(l) --> POCl3(l) + 2HCl(aq)

Group of answer choices

1. oxidation reduction

2. acid base

3. precipitation

Answer 1

The answer to your question is: none

Step-by-step explanation:

PCl₅(s) + H₂O(l) --> POCl₃(l) + 2HCl(aq)

1.- Oxidation reaction

P⁺⁵Cl₅⁻¹(s) + H₂⁺¹O⁻²(l) --> P⁺⁵O⁺³Cl₃⁻¹(l) + 2H⁺¹Cl⁻¹(aq)

It is not an oxidation reduction reaction because the oxidation numbers are the same in the reactants and products.

2.- Acid base

It is not an acid base reaction because none of the reactants is an acid or a base and none of the products is water.

3.- Precipitation

It is not a precipitation reaction because in the products we see that one is a liquid and the other is in solution, to be a precipitation reaction one of the products must be a solid.

Answer 2

2. acid base

Step-by-step explanation:

PCl5(s) + H2O(l) --> POCl3(l) + 2HCl(aq)

1. Oxidation Reduction reactions involve changes in the oxidation number of the elemements present. In the above reaction, there is no change in osidation number.

Oxygen has oxidation number of -2 in both the reactant and product side.

Chlorine has oxidation number of -1 in both the reactant and product side.

Phosphorus has oxidation number of 5 in both the reactant and product side.

So it is not an oxidation reduction reaction.

2. According to Lewis concept, acid is the substance with empty orbital in valence shell so that it can accept electron pair. PCl5 contain empty d orbital in valence shell. Hence it can acts as Lewis acid. Water has lone-pair electrons and is an anion, thus it is a Lewis Base. This means this reaction is an acid-base reaction.

3. A precipitation reaction refers to the formation of an insoluble salt when two solutions containing soluble salts are combined. The insoluble salt that falls out of solution is known as the precipitate, hence the reaction's name. A subtle way of identifying this type of reaction is by looking at the phases of the products. A solid may turn out to be a precipitate. The reaction above has no products in the slid state. So it is not a precipitation reaction.