Select The Correct Answer.Which Statement Correctly Relates Two Substances From This Reaction?$ H_2CO_3 + H_2O \rightleftharpoons H_3O^+ + HCO_3^- $A. $ HCO_3^- $ Is The Conjugate Acid Of $ H_2CO_3 $.B. $ H_2O $ Is
Introduction
In chemistry, acid-base equilibria play a crucial role in understanding various chemical reactions. One such reaction is the dissociation of carbonic acid (H2CO3) in water, which is represented by the equation: H2CO3 + H2O ⇌ H3O+ + HCO3-. This reaction is a fundamental aspect of acid-base chemistry and is essential for understanding various biological and environmental processes. In this article, we will delve into the details of this reaction and explore the correct relationship between the substances involved.
The Carbonic Acid Reaction
The carbonic acid reaction is a reversible reaction, meaning that it can proceed in both forward and backward directions. In this reaction, carbonic acid (H2CO3) reacts with water (H2O) to form hydronium ions (H3O+) and bicarbonate ions (HCO3-). This reaction is an example of a weak acid dissociation, where the acid (H2CO3) partially dissociates in water to produce ions.
Conjugate Acid-Base Pairs
In acid-base chemistry, conjugate acid-base pairs are essential for understanding the relationships between acids and bases. A conjugate acid is the species formed when a base accepts a proton (H+), while a conjugate base is the species formed when an acid donates a proton. In the context of the carbonic acid reaction, we need to identify the conjugate acid-base pairs involved.
Option A: HCO3- is the Conjugate Acid of H2CO3
Let's examine option A, which states that HCO3- is the conjugate acid of H2CO3. To determine if this statement is correct, we need to analyze the reaction and identify the species that accepts a proton. In the carbonic acid reaction, H2CO3 donates a proton to form HCO3-, which means that HCO3- is the conjugate base of H2CO3, not the conjugate acid. Therefore, option A is incorrect.
Option B: H2O is the Conjugate Base of H3O+
Now, let's examine option B, which states that H2O is the conjugate base of H3O+. To determine if this statement is correct, we need to analyze the reaction and identify the species that donates a proton. In the carbonic acid reaction, H2CO3 donates a proton to form H3O+, which means that H2O is the conjugate base of H3O+, not the conjugate acid. However, this is not the correct relationship between H2O and H3O+. The correct relationship is that H2O is the conjugate base of H3O+ because H3O+ is the conjugate acid of H2O.
The Correct Relationship: H2O is the Conjugate Base of H3O+
In the carbonic acid reaction, H2CO3 donates a proton to form H3O+, which means that H3O+ is the conjugate acid of H2O. Therefore, the correct relationship between the substances involved in the reaction is that H2O is the conjugate base of H3O+.
Conclusion
In conclusion, the correct relationship between the substances involved in the carbonic acid reaction is that H2O is the conjugate base of H3O+. This relationship is essential for understanding the acid-base equilibria involved in this reaction. By analyzing the reaction and identifying the conjugate acid-base pairs, we can determine the correct relationship between the substances involved.
Key Takeaways
- The carbonic acid reaction is a reversible reaction that involves the dissociation of carbonic acid in water.
- Conjugate acid-base pairs are essential for understanding the relationships between acids and bases.
- In the carbonic acid reaction, H2CO3 donates a proton to form H3O+, which means that H3O+ is the conjugate acid of H2O.
- The correct relationship between the substances involved in the reaction is that H2O is the conjugate base of H3O+.
References
- Atkins, P. W., & De Paula, J. (2010). Physical chemistry. Oxford University Press.
- Brown, T. E., & LeMay, H. E. (2014). Chemistry: The Central Science. Pearson Education.
- Petrucci, R. H., Harwood, W. S., & Herring, F. G. (2016). General chemistry: Principles and modern applications. Pearson Education.
Frequently Asked Questions: Understanding Acid-Base Equilibria ====================================================================
Q: What is acid-base equilibrium?
A: Acid-base equilibrium refers to the balance between the concentrations of acids and bases in a solution. It is a dynamic process where acids and bases can donate or accept protons, resulting in the formation of conjugate acid-base pairs.
Q: What is the difference between a strong acid and a weak acid?
A: A strong acid is an acid that completely dissociates in water, producing a high concentration of hydrogen ions (H+). Examples of strong acids include hydrochloric acid (HCl) and sulfuric acid (H2SO4). A weak acid, on the other hand, only partially dissociates in water, producing a low concentration of hydrogen ions. Examples of weak acids include acetic acid (CH3COOH) and carbonic acid (H2CO3).
Q: What is the conjugate base of an acid?
A: The conjugate base of an acid is the species formed when the acid donates a proton (H+). For example, the conjugate base of hydrochloric acid (HCl) is chloride ion (Cl-).
Q: What is the conjugate acid of a base?
A: The conjugate acid of a base is the species formed when the base accepts a proton (H+). For example, the conjugate acid of hydroxide ion (OH-) is water (H2O).
Q: What is the pH scale?
A: The pH scale is a measure of the concentration of hydrogen ions (H+) in a solution. It ranges from 0 to 14, with a pH of 7 being neutral (neither acidic nor basic). A pH below 7 is acidic, while a pH above 7 is basic.
Q: What is the relationship between pH and pOH?
A: The pH and pOH scales are related by the equation: pH + pOH = 14. This means that as the pH of a solution increases, the pOH decreases, and vice versa.
Q: What is the Henderson-Hasselbalch equation?
A: The Henderson-Hasselbalch equation is a mathematical expression that relates the pH of a solution to the concentrations of the acid and its conjugate base. It is given by the equation: pH = pKa + log10([A-]/[HA]), where pKa is the acid dissociation constant, [A-] is the concentration of the conjugate base, and [HA] is the concentration of the acid.
Q: What is the significance of the acid dissociation constant (Ka)?
A: The acid dissociation constant (Ka) is a measure of the strength of an acid. It is defined as the ratio of the concentrations of the conjugate base and the acid to the concentration of the hydrogen ion. A high Ka value indicates a strong acid, while a low Ka value indicates a weak acid.
Q: What is the relationship between the acid dissociation constant (Ka) and the pH of a solution?
A: The acid dissociation constant (Ka) is related to the pH of a solution by the equation: pH = -log10(Ka). This means that as the Ka value increases, the pH of the solution decreases, and vice versa.
Q: What is the significance of the pH of a solution in biological systems?
A: The pH of a solution is crucial in biological systems, as it affects the activity of enzymes, the stability of proteins, and the functioning of cells. A pH that is too high or too low can be detrimental to living organisms.
Q: What are some common applications of acid-base equilibria in everyday life?
A: Acid-base equilibria have numerous applications in everyday life, including:
- Food and beverage industry: pH control is essential in the production of food and beverages to ensure their quality and safety.
- Water treatment: pH control is necessary to remove impurities and contaminants from water.
- Pharmaceutical industry: pH control is critical in the development of new medicines and in the production of existing ones.
- Environmental monitoring: pH monitoring is essential in understanding the impact of acid rain and other environmental pollutants on ecosystems.
Conclusion
In conclusion, acid-base equilibria are a fundamental concept in chemistry that has numerous applications in everyday life. Understanding the principles of acid-base equilibria is essential in various fields, including biology, medicine, and environmental science. By grasping the concepts of acid-base equilibria, we can better appreciate the complexity and beauty of chemical reactions and their impact on our world.