Which of the following is an example of a Brønsted-Lowry base?
A. HCl
B. [tex]H _3 O ^{+}[/tex]
C. [tex]NH _3[/tex]
D. [tex]NH _4{}^{+}[/tex]
Answer (2)
The example of a Brønsted-Lowry base from the given options is C. NHâ, as it can accept protons to form NHââş. The other options either act as acids or donât fit the definition of a base. Thus, NHâ is the correct answer.
;
A Brønsted-Lowry base accepts protons.
HCl and H 3 â O + are acids and donate protons.
N H 3 â accepts a proton to form N H 4 + â .
N H 4 + â donates protons.
Therefore, the answer is N H 3 â â .
Explanation
Identifying a Brønsted-Lowry Base Let's analyze the options to determine which one is a Brønsted-Lowry base. Remember, a Brønsted-Lowry base is a substance that can accept a proton (H+).
Analyzing HCl A. HCl: Hydrochloric acid is a strong acid. Acids are proton donors, not acceptors. So, HCl is not a Brønsted-Lowry base.
Analyzing H 3 â O + B. H 3 â O + : The hydronium ion is formed when a water molecule accepts a proton. It acts as an acid by donating a proton. Therefore, H 3 â O + is not a Brønsted-Lowry base.
Analyzing N H 3 â C. N H 3 â : Ammonia has a lone pair of electrons and can accept a proton to form the ammonium ion ( N H 4 + â ). This makes it a Brønsted-Lowry base. The reaction is: N H 3 â + H + â N H 4 + â
Analyzing N H 4 + â D. N H 4 + â : The ammonium ion can donate a proton to become ammonia ( N H 3 â ). This makes it a Brønsted-Lowry acid, not a base.
Conclusion Therefore, the correct answer is C. N H 3 â is a Brønsted-Lowry base because it can accept a proton.
Examples
Brønsted-Lowry bases are essential in many chemical reactions, including acid-base titrations. For example, in a titration, a base like ammonia ( N H 3 â ) neutralizes an acid, allowing us to determine the concentration of the acid. This principle is used in various applications, such as determining the acidity of soil in agriculture or monitoring the pH levels in water treatment plants. Understanding Brønsted-Lowry bases helps us control and analyze chemical reactions in these real-world scenarios.
