Does high pH values break H bonds of a protein or just the ionic bonds?
828553
At physiological pH most of the -COOH of amino acids are deprotonated (-COO-) and -NH2 protonated (-NH3+).\nIf you increase the pH then the -COO- will remain as such but the -NH3+ will lose the proton. -NH3+ can act only as an H-donor for an H-bond so such a bond will be broken. However if the geometry and number of interacting partners allow it it could be replaced by another H of the same -NH2 group.\n\nTyrosine has pKa around 10, so if you go to extremely basic pH it will be deprotonated and thus it will not be able to act anymore as an H-donor for a hydrogen bond and the bond will break. If however it was acting as a lone pair donor, the bond will become even stronger.\n\nGenerally when the pH change (extremely basic or acidic) causes changes in the charge of the group can but not necessarily breaks H-bonds. An important note: even if the H-bonds are not completely broken there will be rearrangement (some bonds might break and others form as the some H-donors become H-acceptors and vice versa) changing the conformation/folding of the protein.\n\nFor sure the effect of pH on ionic bonds is far greater than that on H-bonds.
1122499
pH = pKa - log (.25/.4) ~= 4.3
374165
PH\nFrom Wikipedia, the free encyclopedia\n \npH (potential hydrogen) is a measure of the activity of hydrogen ions (H+) in a solution and, therefore, its acidity or alkalinity. In aqueous systems, the hydrogen ion activity is dictated by the dissociation constant of water (Kw = 1.011 × 10−14 at 25 °C) and interactions with other ions in solution. Due to this dissociation constant a neutral solution (hydrogen ion activity equals hydroxide ion activity) has a pH of approximately 7. Aqueous solutions with pH values lower than 7 are considered acidic, while pH values higher than 7 are considered alkaline
921604
theoretically yes 10m acid has a pH of -1, and 10 moles of base pH 15.\n\nBut , in fact, for very high concentrations, you must not take in account the concentration of ions H+ but the activity . The actvity takes in account the high concentration and is \n\nactivity = gamma * pH where gamma is lower than one for high concentrations
950410
Mainly H-bonding (intermolecular forces)
759910
it forms hydrogen bonds.
445370
well this question was asked two days before.\nsearch for this question u'll get all the knowledge\nstrongest oxo-acid-- HClO4\nstrongest protonic acid--H2SO4\nstrongest lewis acid----SBF5\n btw HF is not consider very strong bcoz F is very small atom and it does not loose H+ very easily.\n\nEDIT: Question(very odd name) there has been acids with negative pH and 0 pH( 0pH is more stronger than 1)
424998
In 1909 a Danish biochemist, by the name of Sorenson, suggested reporting the concentration of H+ ion on a logarithmic scale, which he named the pH scale. Because of the magnitude of these concentrations it has become more convenient to give the acidity in terms of the pH, rather than as [H+]. pH is defined as; \npH = -log [H+] \nThe scale can be adjusted to include pH values at various [H+]. Now an acid can be defined as a substance which when added to water has a pH < 7.00 and base has a pH>7.00.
687922
Actually, if you mean strength as in acidity, a solution with a pH of 5 would be 10 times stronger than one with a pH of 6.\n\nHowever, both would be very weak acids, since neutral is about pH 7.
179057
It's not C.  An increase in pH makes a solution more alkaline, meaning less H+ in the fluids.\n\nI'm going to say A here because a rise in pH is associated with increased O2 binding to hemoglobin.
62342
Acidity is when an excess of H+ binds H2O as H3O+.  Strong acids are ones like HCl, which in solution will ionize completely--Cl-, being very soluble, will let go of H+ to make the solution acidic.  Other "weak" bases are ones that do not necessarily ionize completely.  Excess H+ will bind to sites in the weak acid molecule rather than binding to H20, meaning that the pH will not be as low (low pH < 7 = acidic).  In this way, a weak acid can act as a buffer--in pure water, it will ionize to a certain extent, but with excess H+, it will bind more H+, but the free H+ in solution will only change very little, and the pH remains rather stable.
886933
increased ionic concentration generally means increased acidity which acts the same way as increased temperature on an enzyme causing breakdown of the structure and function.
960642
Look up the chemical in a pKa ( -log of dissociation constant K)table of acids. H2PO4- has a pKa of 7.20. It is not very acidic.
1090773
pH can be calculated for substance which can disassociates into ions(mainly H+ and OH-). Butane is a pure covalent compound and it cannot be ionised. \nFor properties please visit: http://en.wikipedia.org/wiki/Butane
804153
At high pH values (>10), the Hydroxide ion in solution takes protons from the phenolphthalein indicator, forming an ion and water.  The -2 ionic form of phenolphthalein then rearranges the electronic structure to form the characteristic pink color.\n\nSee the wikipedia article for more.
192513
A strong acid, like HCl, might cleave your ethanoic annhydride. That's the only thing I can think of. Phosphoric acid gives you a weak source of protons.
573821
I think this question is incomplete because the Ka of HF hasn't been provided.  The amount of H+ that is formed from HF can only be calculated from its Ka value.