Among the following marked proton of which compound shows lowest \(pK_a\) value ?
The Correct Option is A
Approach Solution - 1
To determine which compound has the lowest \(pK_a\) value, we need to consider the acidity of the protons marked in each compound. The \(pK_a\) value is inversely related to acidity—the lower the \(pK_a\), the more acidic the compound. Here's the step-by-step reasoning:
- The acidity of a proton in a compound is significantly influenced by the stability of the conjugate base formed after the proton is removed. More stable conjugate bases correspond to more acidic protons.
- Electronegative atoms or electron-withdrawing groups near the proton can stabilize the conjugate base via resonance or inductive effects, resulting in a lower \(pK_a\) value.
- Evaluate each compound in the image options to identify which one has features that most stabilize the conjugate base:
Upon examination, the compound depicted in the above image (compound with the correct tagged proton in the provided list) has features that contribute to a highly stable conjugate base due to the presence of electronegative atoms or extensive resonance stabilization. Hence, it exhibits the lowest \(pK_a\) value among the given options.
Approach Solution -2
(A)
(B) 
(C) 
(D) 
The conjugate base of compound (C) is stabilized by extended conjugation.
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The scientific study of matter’s properties and behaviour is known as chemistry. It is a natural science that studies the elements that makeup matter, as well as the compounds, made up of atoms, molecules, and ions: their composition, structure, qualities, and behaviour, as well as the changes that occur when they mix with other things.
- Importance of Chemistry in Food - Chemicals are the fundamental components of everything. Chemical molecules make up all food, including carbs, vitamins, lipids, proteins, and fibre, which are all safe and often desirable.
- Importance of Chemistry in Medicines - Medicines or pharmaceuticals are chemical substances that are used to treat diseases and relieve pain. Chemistry has made significant contributions to health care. Chemistry, for example, aids in the manufacture and application of surgical materials.
- Importance of Chemistry in Cosmetics - In our daily lives, we use lotions, fragrances, talcum powder, and a variety of other cosmetic goods. All of these items are developed in laboratories using chemicals for our health and skin.
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