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  • citric acid
  • δ ¯ = ∑ x i δ i ∑ x i {\displaystyle {\bar {\delta }}={\frac {\sum x_{i}\delta _{i}}{\sum x_{i}}}} Example: the pKa of the hydroxyl group in citric acid has been determined from 13C chemical shift data to be 14.4. (wikipedia.org)
  • The example of citric acid is shown at the right. (wikipedia.org)
  • acidic
  • is a weak acid, some of it will remain in the acidic form. (coursera.org)
  • The amino acid sequence comprises one sequence of 39 amino acidic residues followed by 11 sequences of 40 residues, each of it contains one SRTX sequence preceded by 19 spacer amino acids. (wikipedia.org)
  • Synthetic 3-D macroporous hydrogels shows the excellent ability to adsorb heavy-metal ions in a wide range of pH from extremely diluted aqueous solutions, which can be later used as an adsorbent for purification of salty water All proteins are polyampholytes, as some amino acids tend to be acidic, while others are basic. (wikipedia.org)
  • Chemicals or substances having the property of an acid are said to be acidic. (wikipedia.org)
  • It is the most acidic species that can exist in water (assuming sufficient water for dissolution): any stronger acid will ionize and protonate a water molecule to form hydronium. (wikipedia.org)
  • Unlike hydronium in neutral solutions that result from water's autodissociation, hydronium ions in acidic solutions are long-lasting and concentrated, in proportion to the strength of the dissolved acid. (wikipedia.org)
  • dissociate
  • We have to figure out what fraction for acid dissociate into the ions. (coursera.org)
  • The molecules in pure water auto-dissociate (i.e.: react with each other) into hydronium and hydroxide ions in the following equilibrium: 2 H 2O ⇌ OH− + H 3O+ In pure water, there is an equal number of hydroxide and hydronium ions, so it is a neutral solution. (wikipedia.org)
  • Lewis
  • Finally, the concept of Lewis acids and bases is discussed and demonstrated through examples. (coursera.org)
  • An acid is a molecule or ion capable of donating a hydron (proton or hydrogen ion H+), or, alternatively, capable of forming a covalent bond with an electron pair (a Lewis acid). (wikipedia.org)
  • The second category of acids are Lewis acids, which form a covalent bond with an electron pair. (wikipedia.org)
  • Lewis considered this as a generalization of the Brønsted definition, so that an acid is a chemical species that accepts electron pairs either directly or by releasing protons (H+) into the solution, which then accept electron pairs. (wikipedia.org)
  • In modern terminology, an acid is implicitly a Brønsted acid and not a Lewis acid, since chemists almost always refer to a Lewis acid explicitly as a Lewis acid. (wikipedia.org)
  • Interestingly, although alcohols and amines can be Brønsted-Lowry acids, they can also function as Lewis bases due to the lone pairs of electrons on their oxygen and nitrogen atoms. (wikipedia.org)
  • amino acid
  • Each contains twenty-one amino acid residues that spontaneously fold into a defined tertiary structure with two interchain-cysteine linkages (disulfide bonds) and a long hydrophobic tail. (wikipedia.org)
  • nitrogen
  • Later he worked on acid-base equilibria of organic nitrogen compounds, as well as reaction kinetics. (wikipedia.org)
  • An example is boron trifluoride (BF3), whose boron atom has a vacant orbital which can form a covalent bond by sharing a lone pair of electrons on an atom in a base, for example the nitrogen atom in ammonia (NH3). (wikipedia.org)
  • gastric acid
  • In the human stomach and duodenum, the bicarbonate buffer system serves to both neutralize gastric acid and stabilize the intracellular pH of epithelial cells via the secretion of bicarbonate ion into the gastric mucosa. (wikipedia.org)
  • reaction
  • So, which acid/base reaction you use depends on the exact identity of the acid you're examining. (physicsforums.com)
  • When the system is in equilibrium, the rate of the forward reaction equals the rate of the reverse reaction. (physicsforums.com)
  • Because the reaction is reversible, only a fraction of the acid will be ionized at any one point in time. (dlrgenchem.com)
  • By Le Chȃtelier's Principle, the release of CO2 from the lungs pushes the reaction above to the left, causing carbonic anhydrase to form CO2 until all excess acid is removed. (wikipedia.org)
  • The unifying principle is that the free energy of a system at equilibrium is the minimum possible, so that the slope of the free energy with respect to the reaction coordinate is zero. (wikipedia.org)
  • pairs
  • Includes the meaning of the term conjugate as applied to acid-base pairs. (chemguide.co.uk)
  • SRTXs complete cDNA sequence comprises 1948 base pairs (bp) coding for a pre-pro-polypeptide of 543 amino acids which starts with a methionine that initiates translation followed by a hydrophobic peptide characteristic of a signal sequence. (wikipedia.org)
  • water
  • An acid is a substance that produces H + ions (or equivalently, H 3 O + ions) when dissolved in water, and a base is a substance that produces OH - ions when dissolved in water. (dlrgenchem.com)
  • That is, when molecular HCl dissolves in water, it begins to split into ions, and the process continues until all the acid is ionized. (dlrgenchem.com)
  • In contrast, a weak acid is only partially ionized in water. (dlrgenchem.com)
  • This article aims to create a model to accurately predict the equilibrium partitioning of naphthenic acids and basic crude oil components between the oil and water phase. (bibsys.no)
  • The results show that acid species are more water soluble than basic species of similar molecular weight. (bibsys.no)
  • hydrogen
  • Because the base of the pyramid is made up of three identical hydrogen atoms, the H 3O+ molecule's symmetric top configuration is such that it belongs to the C3v point group. (wikipedia.org)
  • Bjerrum recognised that the formation of a metal complex with a ligand was a kind of acid-base equilibrium: there is competition for the ligand, L, between the metal ion, Mn+, and the hydrogen ion, H+. (wikipedia.org)
  • metabolic
  • The bicarbonate buffer system is an acid-base homeostatic mechanism involving the balance of carbonic acid (H2CO3), bicarbonate ion (HCO− 3), and carbon dioxide (CO2) in order to maintain pH in the blood and duodenum, among other tissues, to support proper metabolic function. (wikipedia.org)
  • Winters' formula, named for Dr. R.W. Winters, is a formula used to evaluate respiratory compensation when analyzing acid-base disorders and a metabolic acidosis is present. (wikipedia.org)
  • compounds
  • The kinetic interfacial tension between heptane and 3.5% NaCl aqueous buffer was also analyzed with oils that contained single compounds, two bases, two acids and all four components over a pH interval to identify any interfacial acid-base interactions. (bibsys.no)
  • molecular
  • After a review of the properties of crude oil acids and bases, the equilibrium partitioning of acids and bases with different molecular weight was analyzed over a pH interval using heptane as the oil phase and 3.5 wt. (bibsys.no)
  • Phenylacetic acid would represent the low molecular weight acid while 4-heptylbenzoic acid was chosen to represent the high molecular weight one. (bibsys.no)
  • The high molecular weight base did not significantly partition into the aqueous phase at the pH range studied. (bibsys.no)
  • esters
  • The migration of the esters induced by DBU results in equilibrium between regioisomers favouring the C2 protected isomer, but NaH induced migration of sulfonyl and silyl groups results in complete migration from equatorial to axial hydroxyl groups. (diva-portal.org)
  • a glycerol molecule attached to three fatty acid esters is called a triacylglyceride. (wikipedia.org)
  • solvents
  • Because the M-O bonds are typically strong and these compounds are crosslinked polymers, the solids tend to be insoluble in solvents, though they are attacked by acids and bases. (wikipedia.org)
  • This is very similar to the process described above, only instead of treating the beans directly, water resulting from the soaking of beans is treated with solvents and the process goes on until equilibrium is reached without caffeine in the beans. (wikipedia.org)
  • This method was first mentioned in 1941, and people have made great efforts to make the process more "natural" and a true water-based process by finding ways to process the caffeine out of the water in ways that circumvents the use of organic solvents. (wikipedia.org)
  • chemical
  • Topics covered include kinetics, thermodynamics, chemical equilibria, acid-base chemistry and nuclear chemistry.Prerequisite: CHE111 or consent of the instructor. (nwciowa.edu)
  • The sensitivity of the 4-isomer was demonstrated to be adequate for determining the small amounts of acid produced in certain chemical dosimeter systems. (unt.edu)
  • protein
  • This volume should prove useful to a large and varied group including the student who wants to know what a protein spectrum looks like, the researcher who would like to know about the 'shift to the red' on removing nucleotide contaminants from a protein, and the analyst seeking to learn where the isosbestic point of a protein in acid and alkali solutions is located. (molbiol.ru)
  • carbon
  • These conversions are as follows: PGD2 is a 20 carbon arachidonic acid metabolite with double bonds between carbons 5,6 and 13,14, a carbon-carbon bond between carbons 8 and 12 (which establishes its cyclopentanone ring), hydroxyl residues attached to carbons 9 and 15, and a ketol residue (i.e. oxygen double bonded to carbon) attached to carbon 11. (wikipedia.org)
  • PGE2 and PGE1 are 20 carbon metabolites of arachidonic acid and dihomo-γ-linolenic acid, respectively, with a double bond between carbons 13 and 14, a carbon-carbon bond between carbons 8 and 12 (which establishes their cyclopentanone structure), hydroxyl residues at carbons 11 and 15, and a ketol residue at carbon 9. (wikipedia.org)
  • Carbon monoxide is the product of the incomplete combustion of carbon-based fuels and precursor to many useful chemicals. (wikipedia.org)
  • complex
  • Some basic types of responsiveness such as reflexes can be mediated by the spinal cord or peripheral ganglia, but sophisticated purposeful control of behavior based on complex sensory input requires the information integrating capabilities of a centralized brain. (wikipedia.org)
  • surface
  • Surface charge density is defined as the amount of electric charge, q, that is present on a surface of given area, A:[full citation needed] σ = q A {\displaystyle \sigma ={\frac {q}{A}}} According to Gauss's law, a conductor at equilibrium carrying an applied current has no charge on its interior. (wikipedia.org)
  • natural
  • The most structurally diverse 2,5-diketopiperazine natural products are based on tryptophan and proline modified by heterocyclisation and isoprenyl addition. (wikipedia.org)