How should the pH of a 0.1M soln of NaC2H3O2 compare with that of a 0.1M soln of KC2H3O2?Explain?
CH3 COO Na is a salt made when NaOH and CH3 COOH react with each other. CH3 COO K is a salt made when KOH and CH3 COOH react with each other. in both cases the alkali is strong and the acid is the same weak acid. when these salts are placed in water, the conjugate base from the weak acid (CH3 COO-) is involved in hydrolysis reaction. the K+ and Na+ produced do not react with water. hence the final pH of the solution will be the same in the two salts.
How should the pH of a 0.1M solution of NaC2H3O2 compare with that of a 0.1M solution of KC2H3O2?
All other things being equal the two compounds should make solutions with the same pH. That is because it is the hydrolysis of the acetate ion, C2H3O2^-, that determines the pH. C2H3O2^-(aq) + H2O(l) = HC2H3O2(aq) + OH^-(aq) Kh = base hydrolysis constant = [HC2H3O2][OH^-]/[C2H3O2^-] = Kw/Ka Ka for acetic acid, HC2H3O2 = 1.80 x 10^-5 Kh = (1.00 x 1-^-14)/(1.80 x 10^-5) = 5.56 x 10^-10 Since the equilibria are identical for the two salts the pH of their solutions will be the same if you start with pure substances. If the salts are contaminated with acetic acid or extra OH^- then the solutions will seem to have different pHs.
How should the pH of a 0.1M solution of NaC2H3O2 compare with that of a 0.1M solution of KC2H3O2?
The sodium ion and the potassium ion do not affect the pH. So, the pH of the 2 solutions are equal. According to the 2 websites below, the pH is approximately 8.9 http://au.answers.yahoo.com/question/ind... http://in.answers.yahoo.com/question/ind... Acetic acid is a weak acid. So the acetate ion attracts an H+ from the water. As H+’s are removed from the solution, the pH increases. For the positive ion to affect the pH, it must bond with the OH-1 ions in the water. Magnesium and Calcium ion bond with the OH-1 ions to form precipitates. As OH-1 ion are removed from the solution, the pH decreases. Sodium and Potassium ions do not form insoluble hydroxides. So, they do not affect the pH. According to the website below, the pH of 0.1 Mg(C2H3O3)2 is approximately 8.5 http://www.sigmaaldrich.com/catalog/prod... The Mg+2 ions have bonded with OH-1 ions. Now the solution has less OH-1 ions. So the pH has decreased from 8.9 to 8.5. According to the website below, the pH of 0.1 Ca(C2H3O3)2 is approximately 7 http://www.sigmaaldrich.com/catalog/product/sigma/39719?lang=en®ion=US Since the pH is 7, the number of H3O+1 ions is equal to the number of OH-1 ions. This means the affect of the calcium ion counter acted the affect of the acetate ion! I hope this helps you!
Calculate the pH of a 0.500 M solution of KCN. Ka for HCN is 5.8 x 10^-10?
KCN is a salt of weak acid(HCN) and strong base(KOH). Use the relation for hydrolysis of salt of weak acid and strong base.pH=7+0.5(pKa+logC)Put the values and get answer.
How should these 2 pH's compare?
same pH, both are salts of the same weak acid. The Na and K play no role in making the pH be different.
If the pH of a solution is decreased from 9 to 8, what does it mean?
a. concentration of H+ has decreased 10 times what it was at pH 9. b. concentration of H+ has increased 10 times what it was at pH 9. c. concentration of OH- has increased 10 times what it was at pH 9. d. concentration of OH- has decreased 10 times what it was at pH 9. e. B and D are correct
Comparing pHs?
Should have the same pH.
AP Chemistry help! Rank the following .10 M solution in order of increasing pH.?
Bee, this question has been one of the questions which YA sends to me because they think I know something about chemistry, and I have been avoiding answering it because I'm not sure of "c." But since no-one else has come forward, let me try. Okay, the first two aren't so hard, in"a" HF is a strong acid and would have the lowest pH. HI is also an acid, but it doesn't ionize to the extent that HF does, and I believe there's some hydrolysis that takes place. NaF is the salt of a strong acid and a strong base and probably has a pH of 7. Finally, NaI would involve some of the hydrolysis I referred to earlier and would therefore be basic (i.e. a strong base and a weak acid). "b" isn't too bad either. HBr is a fairly strong acid and would have the lowest pH. NH4Br would probably be somewhat acidic because NH4OH is a weaker base when compared to HBr as an acid, so the NH4+ ions would tie up more OH- ions from the water solution than the consequent hydrolysis of the Br- ion. Finally, NH3 would form NH4+ ions and probably release more OH- ions than any of the others so it would be the most basic and have the highest pH. Now I'm on shaky ground, first of all, HNO3 is a very strong acid and definitely has the lowest pH; NaOH is a very strong base and will have the highest pH. Then comes aniline, then phenol (C6H5OH), then sodium nitrate (which should have a ph of 7), and then KOC6H5, and then, as I've said, comes NaOH. That's the best I can do, Bee: I'm pretty sure I'm right, but I wish someone else had tried to help you. Since it's been three days with no-one else trying, I did my best. As for Alex, bless his heart! He's trying to help, but I'm afraid he's wrong.