The lab report "How Molecule’s Structure affect the pKa?" discusses a molecule’s structure effect on the pKa of Its ground and excited States. The structure of a molecule is widely believed to have a considerable influence on the pKa of Its Ground and Excited States. This is particularly attributed to the energy relationships between the ground and excited states of various organic acids in both their deprotonated and protonated forms. According to many experts, the electronic structure of a molecule can determine both its physical and chemical properties as well as the potential charge distribution, ionization potential, geometry, electronic affinity and ultimately, chemical reactivity. In this regard, any change in the electronic structure of a molecule may be expected to alter the chemical or physical properties. Generally, this is what usually occurs when molecules are raised to an electronically excited state through the absorption of quantum light such as photons with an energy that matches the energy gap between the exited and ground states. 2-naphthol, also known as β-naphthol or ArOH is a fluorescent, colorless and water-soluble solid that can effectively be used to help determine the potential energy relationships between the protonated and deprotonated forms of organic acids and their ground and excited states. The reagents that were used in the experiment included 1.0 M ammonium hydroxide buffer solution (NH4OH), 1.0 M ammonium chloride (NH4Cl) and 0.10 M hydrochloric acid (HCl).