A. H3PO4 (aq) and KOH(aq) Express your answer as a chemical equation including phases. = AEO ?
Enter a balanced molecular equation for the neutralization of each of the following.
B. What is the role of the reagent used in here.
?? CI ?? CI
a. Acid
b. Base
c. Nucleophile
d. Electrophile
The Correct Answer and Explanation is :
Balanced Chemical Equation for the Neutralization Reaction
A. Reaction Between H₃PO₄ (aq) and KOH (aq):
Phosphoric acid ((H_3PO_4)) reacts with potassium hydroxide ((KOH)), a strong base, in a neutralization reaction to form water and a salt (potassium phosphate). The balanced molecular equation is:
[
H_3PO_4 (aq) + 3KOH (aq) \rightarrow K_3PO_4 (aq) + 3H_2O (l)
]
B. Role of the Reagent in the Reaction
In the context of this reaction, the reagent plays the role of either an acid, base, nucleophile, or electrophile.
- Acid (Correct Answer)
- Phosphoric acid (H₃PO₄) is the acid in this reaction.
- It donates hydrogen ions (H⁺) in solution.
- Acids react with bases to form salt and water in a neutralization reaction.
- Base
- Potassium hydroxide (KOH) is the base in this reaction.
- It provides hydroxide ions (OH⁻) that react with H⁺ from the acid.
- Nucleophile (Not the best answer here)
- A nucleophile donates a pair of electrons to form a new bond.
- Hydroxide ions (OH⁻) can act as nucleophiles, but in this case, they primarily act as a base.
- Electrophile (Not the best answer here)
- Electrophiles accept electron pairs in reactions.
- H⁺ ions from H₃PO₄ could be considered electrophilic, but in acid-base reactions, the acid primarily donates protons rather than behaving as an electrophile in a traditional organic chemistry sense.
Explanation of the Reaction (300 Words)
Neutralization reactions occur when an acid and a base react to form water and a salt. In this case, phosphoric acid (H₃PO₄) reacts with potassium hydroxide (KOH). Phosphoric acid is a triprotic acid, meaning it has three hydrogen ions (H⁺) available to donate. Potassium hydroxide is a strong base, which means it dissociates completely in water to release hydroxide ions (OH⁻).
The reaction proceeds as follows:
- H₃PO₄ donates protons (H⁺), acting as an acid.
- KOH provides hydroxide ions (OH⁻), which act as a base.
- The H⁺ from the acid combines with OH⁻ from the base to form water ((H_2O)).
- The remaining phosphate ions (PO₄³⁻) combine with potassium (K⁺) to form potassium phosphate ((K_3PO_4)), a soluble salt.
This reaction is classified as a neutralization reaction, a fundamental acid-base interaction in chemistry. The complete neutralization of one molecule of phosphoric acid requires three molecules of KOH because each KOH provides one OH⁻ ion, and H₃PO₄ has three protons to neutralize.
Conclusion
The role of the reagent depends on which substance you consider:
- H₃PO₄ is the acid because it donates H⁺.
- KOH is the base because it provides OH⁻.
- In this context, the acid-base roles are more relevant than nucleophilic or electrophilic behavior.