A: Extensive property:The property that depends on the amount of matter in a sample is said to be exten Q: What are the bond-line formulas for the following compounds? A: Bond line formula has to be drawn for the given compounds.
Condensed structure is the line diagram, A: A chemical reaction is symbolic representation of the conversion of substances to new substances. Q: The concentration of carbon monoxide CO , a common air pollutant, is found in a room to be 5. A: The volume of the room is calculated as following,. The maximum A: The reaction of NO gas with oxygen gas results in the formation of nitrogen dioxide gas. The corresp Q: How do I do conversions from a problem such as: Many pharmaceuticals are dispensed in elixirs with t A: Density of a substance is defined as the mass of a substance present in the given volume of solution A: A sample of Fe of mass amu.
The number of atoms of Fe in a sample is to be calculated. Q: How do you convert A: The density is given as A: The equilibrium constant can be calculated as per the following equation,. Q: The mass of a beaker is 5. After 5. A: Density is physical quantity that can be determined with the help of mass and volume of the given su Q: how many protos neutrons and electrons make up a neatural atom? A: A neutral atom is made up of protons, electrons and neutrons.
While electrons carry a negative charg What is the density of the honey? Q: I need help with the question attached below. A: The exposure to LD50 leads to the death of half of the population. The LD50 oral dose required to ki Q: A piece of copper has a volume of L what is mass of sample in grams. For the problem it gives me Q: A chemist adds 0. Calculate t What are the reagents? A: Propene is an unsaturated hydrocarbon with three carbon atoms and one double bond between bonded car Q: The solubility is A: Given, the solubility is Q: A water heater contains 54 gal of water.
How many kilowatt-hours of energy are necessary to heat the A: Step 1-We have to calculate the value of energy in kilowatt hours necessary to heat the given water Q: Place the following numbers in scientific notation, rounded to 3 significant digits. A: Rules for significant figures are:All non-zero digits are significant. Q: In an engineering reference book, you find that thedensity of iron is 0. Availability of protein-derived amino acids as feedstock for the production of bio-based chemicals.
Biomass Bioenergy , 44 , — , DOI: Elsevier Ltd. This review describes different potential sources for amino acids that could be used for the prodn. The investigated sources are maize and wheat DDGS, sugarcane vinasse and its leaves, sugar beet vinasse and its leaves, cassava leaves, press cakes of rapeseed, sunflower, soybean, palm oil and Jatropha, animal slaughter waste, microalgae, macroalgae, grass and alfalfa.
It can be concluded that there are enough sources available to produce bio-based chems. Bulk chems. However, it is still necessary to find cost-effective methods for the isolation of amino acids from the discussed sources. Google Scholar There is no corresponding record for this reference.
Environmental comparison of biobased chemicals from glutamic acid with their petrochemical equivalents. American Chemical Society. Glutamic acid is an important biofuels prodn. It is an interesting starting material for synthesis of bio-based chems. This work compared the environmental impact of 4 bio-based chems. A consequential life cycle anal. Removed glutamic acid was substituted with cane molasses and ureum.
A comparison among the 4 bio-based and petrochem. For the latter 2, an optimized computed scenario showed the process for SCN can be improved to a level at which it can compete with the petrochem.
For bio-based ACN, large improvements are required to make it competitive with its petrochem. Results of this life cycle anal. Currently, most methods to produce bio-based products are bio-technol.
Solubility of four amino acids in water and of four pairs of amino acids in their water solutions. Data , 37 , — , DOI: The soly. The eutectic compns. Solubility of -amino acids in water under high pressure: glycine, -alanine, -valine, -leucine, and - isoleucine. Fluid Phase Equilib. Elsevier Science B. The std.
A variety of soly. The l-valine and l-isoleucine have a soly. Pressure coeff. In this work thermodn. Osmotic coeffs. Amino-acid soly. Considered aq. The data show that the salt influence is more pronounced on osmotic coeffs. The electrolyte Perturbed-Chain Statistical Assocn. Without fitting any addnl. Data , 60 , — , DOI: The molal solubilities, d. From the values of the measured refractive indexes, molal solubilities, and the densities, the excess refractive indexes, the molar refractions, the polarizabilities, and the apparent molar volumes of the systems under study were calcd.
The solvation of the amino acids under study was discussed in terms of their molal solubilities, apparent molar volume, and refractive index data.
The phase diagrams of the studied tricomponent systems water-salt-amino acid were also detd. The effect of the electrolytic solns. A salting-in effect of the electrolytic solns. Solution Chem. Data , 57 , — , DOI: Generally the soly. The two forms were found to be enantiotropically related, and the transition temp. Data , 51 , — , DOI: The solubilities at At high and low pH, the solubilities increase remarkably. The solubilities generally decrease with an increase of the concns.
As the NaCl concn. Solubility of alpha-form and beta-form of L-glutamic acid in different aqueous solvent mixtures. Elsevier B. Based on the soly. Solubility of L-phenylalanine in water and different binary mixtures from The results obtained from these measurements were correlated with the temp. Both of the models demonstrated good fitting with the exptl.
In addn. Water was a better solvent for L-phenylalanine than methanol and ethanol, which could thus be used as effective anti-solvents in the crystn.
For all the cases studied, the values of both the std. Solubility of Inorganic and Organic Compounds , 3 rd ed. Effect of acids and bases on the solubility of amino acids. The effect of acids and bases on the soly. It was obsd. However, at higher concns.
For all the amino acids considered here the soly. Solubilities of L-cystine, L-tyrosine, L-leucine, and glycine in aqueous solutions at various pHs and NaCl concentrations. Data , 41 , — , DOI: The NaCl concn. In particular, the addn.
The anal. For the amino acids examd. Correlation of amino acid solubilities in aqueous aliphatic alcohol solutions. The successful description of sepn. An investigation into the correlation of the soly. The measured solubilities of glycine, L-alanine, L-isoleucine, L-phenylalanine, and L-asparagine monohydrate in aq.
It is also noted that the excess soly. Mechanism of polyol-induced protein stabilization: solubility of amino acids and diglycine in aqueous polyol solutions.
The solubilities of several amino acids and diglycine were measured in water and at several concns. The free energy of transfer to aq.
Moreover, the linear polyols appeared to stabilize the hydrophobic interaction more effectively and the peptide-peptide H bond less effectively with increasing chain length of polyols. A cyclic polyol, inositol, has a very strong stabilizing ability on hydrophobic interactions of all nonpolar side chains, but it may act as a destabilizing reagent for peptide-peptide H bonds.
Protein stabilization by polyols is evidently a manifestation of polyol-induced strengthening of the hydrophobic interactions of protein mols. The solubilities of several amino acids and diglycine were measured in aq. The free energy of transfer was pos. The corresponding enthalpies and entropies of transfer, which were measured calorimetrically, were pos. Thus, as well as other polyols and sugars, maltitol could stabilize protein structures through strengthening of the hydrophobic interaction.
The thermal stability of a model protein, RNase A, increased with increasing concns. The solubilities of 11 amino acids, 2 peptides, and 2 carbobenzoxy derivs. The data have been treated so as to yield the effect of urea on the free energy of solvent interaction which accompanies the insertion of a glycyl residue into an existing mol.
The sum of these free energies should be approx. Nonpolar side chains were found to give rise to increased soly. The max. Polar side chains contg. The actual change in free energy of solvent interaction attributable to insertion of a glycyl residue depends on the nature of the mol. The data as a whole account for the denaturing action of urea on globular proteins as being due to stabilization of the unfolded form of a protein mol. The solubility of amino acids and related compounds in aqueous ethylene glycol solutions.
The solubilities of several amino acids, peptides, and carbobenzoxy and benzoyl derivs. The data show that ethylene glycol is less effective than urea in reducing the free energy of hydrophobic interactions between non-polar groups and water. Moreover, ethylene glycol increases the free energy of contact between peptide groups and the solvent, in contrast to urea, which decreases it. These results, when incorporated into the equation for the free energy of unfolding of proteins, which was derived in an earlier paper, show that ethylene glycol must be a much less effective denaturing agent than urea.
The data suggest that when denaturation does occur at very high glycol concns. These conclusions agree with exptl. The solubilities of certain amino acids in water, the densities of their solutions at twenty-five degrees, and the calculated hears of solution and partial molal volumes. The solubility of the amino acids in water. Acetonitrile-protein interactions: amino acid solubility and preferential solvation. Acta, Protein Struct.
The free energy of transfer from water to aq. AN was neg. A parallel examn. At all solvent compns. These results are discussed in relation to the role of AN as an eluting org. Measurements and modelling of the solubility of a mixture of two amino acids in aqueous solutions. Measurements were performed to det.
The results show that for these systems the soly. Comparison of the results obtained in this work with those reported in previous studies, indicates that the soly. A model has been developed to correlate the solubilities of an amino acid in aq.
The activity coeffs. An NRTL and a perturbed hard sphere model, with two amino acid-amino acid adjustable interaction parameters, were used.
The water-amino acid interaction parameters in the NRTL model for the amino acids with low solubilities, namely DL-aspartic acid and DL-phenylalanine, were set to zero. Both activity models can accurately correlate the soly. It was found that, at amino acid concns.
Quantitative investigations of amino acids and peptides. Academic Press Ltd. The concn. For the same variation of sodium chloride concn. A simple relation between the ratio of the solubilities of the amino acids with, and without, salt and NaCl concn.
The relation predicts well the solubilities of L-cystine, L-tyrosine, L-leucine, and glycine in aq. The effects of various solvents and pH on the solys. The aq. A low nonaq. In aq. A distinct increase in soly. In the alc. Establishment of a hydrophobicity scale. The solubilities of amino acids, diglycine, and triglycine were measured in H2O, aq.
EtOH, and dioxane solns. Free energies of transfer of amino acid side chains and backbone peptide units from H2O to EtOH and dioxane solns.
The results show the similarity between the effects of EtOH and dioxane on the stability of those side chains and peptide units. Temperature coefficient of solubility of some clycyl peptides in water-ethanol mixtures. The modified Apelblat equation was found to regress the soly. The Van't Hoff equation was used to calc.
The expt. The more alkyl groups present, the more non-polar the amino acid will be. This effect makes valine more non-polar than alanine; leucine is more non-polar than valine. Rank the following according to increasing non-polarity i. Side chains which have various functional groups such as acids, amides, alcohols, and amines will impart a more polar character to the amino acid. The ranking of polarity will depend on the relative ranking of polarity for various functional groups as determined in functional groups.
In addition, the number of carbon-hydrogens in the alkane or aromatic portion of the side chain should be considered along with the functional group. Example: Aspartic acid is more polar than serine because an acid functional group is more polar than an alcohol group. Example: Serine is more polar than threonine since threonine has one more methyl group than serine. The methyl group gives a little more non-polar character to threonine.
Example: Serine is more polar than tyrosine, since tyrosine has the hydrocarbon benzene ring. List all amino acids by abbreviation which are considered somewhat polar. Rank the following amino acids by increasing polarity. Answer Isoleucine has more CHs, therefore more insoluble than ala. Which amino acid is most soluble in water: lys or ser?
Answer Ser, alcohol group is more polar than amine in lys. Acid - Base Properties of Amino Acids:. If the side chain contains an acid functional group, the whole amino acid produces an acidic solution.
Normally, an amino acid produces a nearly neutral solution since the acid group and the basic amine group on the root amino acid neutralize each other in the zwitterion.
If the amino acid structure contains two acid groups and one amine group, there is a net acid producing effect. The two acidic amino acids are aspartic and glutamic. If the side chain contains an amine functional group, the amino acid produces a basic solution because the extra amine group is not neutralized by the acid group.
Amino acids which have basic side chains include: lysine, arginine, and histidine. Amino acids with an amide on the side chain do not produce basic solutions i.
Since an amino acid has both an amine and acid group which have been neutralized in the zwitterion, the amino acid is neutral unless there is an extra acid or base on the side chain. If neither is present then then the whole amino acid is neutral. You need to look at the functional groups carefully because an amide starts out looking like an amine, but has the carbon double bond oxygen which changes the property.
Amides are not basic. Even though tryptophan has an amine group as part of a five member ring, the electron withdrawing effects of the two ring systems do not allow nitrogen to act as a base by attracting hydrogen ions.
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