Question

Write the conjugate base for each of the following acids: a. \(\mathrm{H}_{2} \mathrm{~S}\) b. HS \(^{-}\) c. \(\mathrm{NH}_{3}\) d. \(\mathrm{H}_{2} \mathrm{SO}_{3}\)

Short answer

The conjugate bases of the given acids are: a. HS\(^-\) b. S\(^{2-}\) c. NH\(_2^-\) d. HSO\(_3^-\).

Step-by-step solution

a. Conjugate base of H\(_2\)S

To find the conjugate base of H\(_2\)S, we remove one hydrogen ion (H\(^+\)) from the acid: H\(_2\)S - H\(^+\) \(\rightarrow\) HS\(^-\).

b. Conjugate base of HS\(^-\)

To find the conjugate base of HS\(^-\), we remove one hydrogen ion (H\(^+\)) from the acid: HS\(^-\) - H\(^+\) \(\rightarrow\) S\(^{2-}\).

c. Conjugate base of NH\(_3\)

To find the conjugate base of NH\(_3\), we remove one hydrogen ion (H\(^+\)) from the acid: NH\(_3\) - H\(^+\) \(\rightarrow\) NH\(_2^-\).

d. Conjugate base of H\(_2\)SO\(_3\)

To find the conjugate base of H\(_2\)SO\(_3\), we remove one hydrogen ion (H\(^+\)) from the acid: H\(_2\)SO\(_3\) - H\(^+\) \(\rightarrow\) HSO\(_3^-\). So, the conjugate bases of the given acids are: a. HS\(^-\) b. S\(^{2-}\) c. NH\(_2^-\) d. HSO\(_3^-\).

Key concepts

Acid-Base Chemistry

Acid-base chemistry is a core concept in chemistry that revolves around the transfer of hydrogen ions ( H^+ ) between substances. This process is fundamental in understanding how acids and bases interact to form conjugate pairs.

Acids are substances that can donate a proton (or hydrogen ion), while bases are substances that can accept a proton. When an acid donates a hydrogen ion, it transforms into its conjugate base. On the other hand, when a base accepts a hydrogen ion, it becomes its conjugate acid.

The concept of conjugate acid-base pairs implies that acid and base reactions are reversible. Essentially, these reactions can proceed both forwards and backwards, leading to an equilibrium state in a closed system. Understanding acid-base chemistry is essential for predicting the behavior of chemical systems in solutions, especially in regards to pH and reactivity.

Hydrogen Ion

The hydrogen ion, often represented as H⁺, plays a crucial role in the formation of acids and bases. In chemistry, a hydrogen ion is essentially a proton, because after losing its single electron, a hydrogen atom is left with only one proton in its nucleus.

In the context of acids, the hydrogen ion is the particle that is donated to another substance. This donation process defines the acidic property of a substance. Conversely, in bases, the ability to accept a hydrogen ion showcases the basic characteristic.

It is also important to note that the behavior of hydrogen ions affects the pH level of a solution. Solutions that have an excess of hydrogen ions are acidic and have a lower pH value, while those with fewer hydrogen ions are basic with a higher pH. This is why managing the concentration of hydrogen ions in a solution is key in fields like biochemistry and environmental science.

Chemical Reactions

Chemical reactions involve the rearrangement of atomic connections between molecules, resulting in new products. Reactions can include participants with either acid or base properties, which determine the resulting chemical compounds.

In acid-base reactions, one of the primary outcomes is the formation of a conjugate base when an acid donates a hydrogen ion. This highlights the importance of chemical reactions in transforming substances and affecting their physical and chemical properties.

A deeper understanding of chemical reactions provides insights into reaction mechanisms and the conditions necessary for reactions to proceed. For instance, certain reactions might require catalysts, appropriate temperature, or pressure conditions. Comprehending these factors can aid in predicting reaction outcomes, synthesizing new compounds, and optimizing industrial chemical processes.