What is the concentration of OH- ions in saturated limewater if [H3O+] = 3.98 × 10-13 M? Is limewater acidic,
602416
http://www.scienceaid.co.uk/titration.html
754616
NaOH is a strong base that forms hydronium ions (H3O) when introduced to oxacilic acids.  If you know the equation that relates pH to hydronium ion concentration you should be able to calculate the exact change.
511319
NaOH is in excess\n\nSubtract moles of H+ from OH- (.0345 mol OH- - .025 mol H+ = .0095 mol OH-)\n\nDivide by total volume (.0095 mol OH-/.0595 L = 0.1596 M)\n\nFind pOH = -log [OH-] = -log [.1596] = 0.7967\n\nFind pH = 14-.7967 = 13.20
407734
Hummm:  You can calculate the [OH-] from the pH.  [OH-] = 10^-2.  pH + pOH = 14 (from [H+]x[OH-] = 10^(-14):  pOH = 14 - 12 = 2.  Find the solubility product for iron (III) hydroxide in a table in the back of your textbook or a handbook of Chemistry or physics. Kp = [Fe+3] x [OH-]^3. Substitute numbers in and solve for [Fe+3].  This is also the molar solubility as one mole of iron hydroxide contains one mole of Fe+3.
812718
A\n\nThe pOH of a solution is the negative log of the concentration of OH ions.  THis would be 9 in this case.  The pOH is the opposite of pH.  The scale is from 0 - 14.  The lower the pOH, the more basic the solution is.  pOH of 7 is neutral.  Lower than 7 is basic and higher than 7 is acidic.  If the pOH of a solution is 9,  the pH of the solution is 5.  The pOH and the pH should add up to be 14.  I hope this helps.
211023
wow, well put mrjeffy! I have one thing to add though. Because all acids and bases are electrolytes, you can use pH to determine what is and isn't an electrolyte in a solution. If it come out as acidic or basic, it is and electrolyte(the darker, the more basic or acidic). If it comes out neutral, like Distilled Water, it is not. Also don't forget that non-electrolytes will not completely dissolve into solution in water.
907196
The concentration of H+ is 3.0 x 10^-4, so you know that the pH will be around 4.  What you need is a calculator that has a LOG button to convert the 0.0003 to an integer value.\n\nSo on your calculator you press the LOG button and then type in 0.0003 and then a ")" and press ENTER.  \n\nYou should get a result that says: -3.522878745 or so.  You need to round off to -3.5 and since pH is the NEGATIVE log of the hydrogen ion concentration you get rid of the minus.\n\nThe answer is 3.5.\n\n1x10^-3.5 is approximately equal to 0.0003.
1108880
HCl   +  NaOH   ===   NaCl   +   H2O\n0.0015 ,  0.0016 ,             0        ,       0        at start of reaction (moles)\n0,           0.0001 ,            0.0015 ,    0.0015  at end of reaction(moles)\n\nevery mole of water contributes about 10^-7(ten to the power -7)\nmoles of OH-  and H+ . thus their contribution to the pH is neglected when there is a considerable amount of acid or base present  i.e more than 10^-5 moles/litre (not moles but CONCENTRATION)\nThus concentration of NaOH = 0.0001/90*1000 moles/litre{total volume = 50+40 ml} = 0.001 .\nas NaOH is a strong electrolyte like any other sodium compound  we can assume complete ionisation . thus[OH-]=[NaOH] = 0.001. now pH = -log[H+]=14-(-log[OH-])= 14+log[OH-]  =14+log[0.001]=11\nthus the pH=11
265538
well, the [H+] (which is the same as [H3O+]) concentration and the [OH-] concentration always add up to 1.0x10^=14. so an equation for that would look like\n\n[H+] x [OH-] = 1.0x10^-14\n\nso just divide 1.0x10^-14 by your concentration of H30+. its as easy as taht!
949431
0.001 = 10^-3  => 14-3=11=PH
804094
dissociation of co2 in water produces produces an acid proton:\n\nCO2 + H2O ⇌ HCO3− + H+\n\nKa = 4.30×10−7 mol/L; pKa = 6.36. \n\nwithout knowing the amount of CO2 or water you used, it is impossible to calculate the pH.\n\nassuming its a 0.1M solution (0.1mol of CO2 dissolved in 1dm³ of water), pH would be around 3.7, whereas strong acids would hit pH 0 at far lower concentrations.
786992
b) small fraction of the maximum number of possible hydronium ions, H3O+.\n\nHNO2 + H2O <===> H3O+ + NO2-
750517
if a soln is acidic it will be the OH anions which will be less.....for a soln 2 b acidic it has to hav H- ions...............
713454
The H3O+ concentration has to be the same as the acetate ion concentration, that is 0.425. Since you don't tell the units I cannot calculate the pH. Why do you need to know pKa of acid if you already know the concentration of the acetate ions? This is a chemistry question. Why don't you place it under chemistry?
313595
Water... its got a pH=7
664234
NH4ClO4 --> NH4^+ + ClO4^-\n\nNow in a water solution,\nClO4^- + H2O --> HClO4 + OH- --> This doesn't happen because HClO4 is a strong acid.  Therefore the only contribution to the pH is from the NH4^+\n\nNH4^+ <=> NH3 + H^+\nYou start with [NH4^+] = 0.40 M, and [NH3]=[H^+] = 0 M; after undergoing equilibrium [NH4^+] = 0.40 - x, while [NH3]=[H^+] = x; Ka = [NH3][H^+]/[NH4^+] = (x)(x)/(0.40-x) = Kw/Kb = (1 x 10^-14)/(1.8 x 10^5)\nAssume x << 0.40, so x^2/0.40 = 5.56 x 10^-10\nx = 1.49 x 10^-5 M = [H^+]\npH = -log(1.40 x 10^-5) = 4.827
914690
a) You friend is wrong. Even pure water has some OH- and H3O+ ions. The concentrations are very low (10^-7), but they are there.\n\nb) There is Clorine in Clorox (sodium hypochlorite), and the bleaching reaction causes oxidation.