PH

The determination of the pH of a buffer solution and the pKa for of a weak acid Introduction A practical was carried out to show how the Henderson-Hasselbalch equation works and to apply and hone the skills of pipetting, buffer-making, pH-meter use and graphing. The primary goal of the practical was to determine the pKa value of a weak acid. The Ka is an acid dissociation constant, it is a quantitative measure of the strength of an acid in solution. The pKa is defined as the negative log of…

ocean intrigues me. I have never been one for loving ocean creatures, but I do enjoy learning about the world below us. I found several facts interesting as I read the articles including: how osmosis and salinity functions, how seawater cells move, how pH affects the ocean, how decomposition works in the environment, how upwelling stirs up nutrients, and how water temperature affects organisms. One of the interesting facts discusses why osmosis and salinity impact marine organisms. Osmosis…

strong-weak titrations allow for an in depth analysis of the half-equivalence point as well as buffers. The half equivalence point allows the calculation of pH from pKa, as they are both equal at the half equivalence point, proven by the Henderson Hasslbach equation. It was Henderson in 1908 that created an equation allowing for the logarithmic calculation for pH from a buffer and the pKa which consequently lead to the knowledge and applications of buffers that we have today. Buffers were also…

change in pH of the non-renewable resources and leads to a destruction in the ecosystem. Specially in agriculture, crops cannot grow in acidic soil, so it is crucial to maintain the acidity of the soil at a neutral state. Consequently, farmers use lime fertilizers such as powdered limestone, CaO, or the ashes of burnt wood to neutralize the acid in the soil. However, considering that the change in acids…

it ionized into gibberellin and H+ ions. Buffered and unbuffered gibberellic acid 5000 mg/L stock solutions were used for spiking exposure jars. The buffered stock solutions were buffered with sodium bicarbonate until the solution reached a neutral pH. Glass jars were filled with moderately hard water and spiked with the appropriate amount of the gibberellic acid 5000 mg/L stock solution to total 100 mL. As an example, the 625 mg/L concentration had 12.5 mL of gibberellic acid 5000 mg/L stock…

affected by pH; the carboxyl groups have poor reactivity to EDC/NHS at pH <4.5, and NHS-esters are more susceptible to hydrolysis at alkaline pH values [18,19,20,41]. The amidation reaction of NHS-ester with amino groups is known to be most efficient at the pH values between 6 and 8; amino groups exhibit poor nucleophilicity to NHS-ester at low pH because of the formation of protonated amino groups, but amino groups have strong nucleophilicity, whereas NHS esters are unstable at high pH…

Introduction A hydrogel is a jelly-like material made of a network of polymer chains capable of absorbing a significant amount of water; enough to make water constitute 40 to 90% of the material’s weight. Hydrogels have numerous applications but among their most noteworthy are those related to the medical field.1 Numerous hydrogels exhibit a high degree of biocompatibility, making them particularly suitable for controlled and sustained release drug formulations.1,2 The wide variety of hydrogels…

Thus, the letters pH stand for “power of hydrogen”. More simply put, pH is the measure of acidity or basicity of the solution. pH is the level of acidity on a scale of 0 to 14 in which 0 is the most acidic while 14 is the most basic. To put it in perspective, the pH value of pure water is 7, the pH value of hydrochloric acid is 0, and sodium hydroxide is around 14. The range of 0 to 14 uses the practical limits that pH puts on some solutions. This means that some solutions…

bioavailability. This required the use of normal aspirin tablets, aspirin tablets with sodium bicarbonate, soluble aspirin, and enteric coated aspirin. Depending on which group the students were allocated they administered different formulations of aspirin. The pH and the concentration of salicylate in each urine sample, collected at different time points, was determined after administering the drug. A standard curve for salicylate was generated to calculate its concentration in each urine…

Number: V00827823 The effect of different pH and temperature levels on the activity and action of catechol oxidase used from a solanum tuberosum specimen Abstract The various effects of temperature and pH on the enzyme activity and action of catechol oxidase, an enzyme containing copper which oxidizes phenols such as catechol with the use of dioxygen, were examined throughout several trial procedures. The experiment was conducted to determine the optimal pH for an enzyme to carry out its…