Consider a solution of potasium hydroside andasolution of alcium bhydroxide. Bot
ID: 1031092 • Letter: C
Question
Consider a solution of potasium hydroside andasolution of alcium bhydroxide. Both solutions have the same molarity. Which solution has the higher ph? 10 The pH of a 0.22 M hypobromous acid solution is measured to be 4.63 What is the Ka of HOBr? uu? 11What is the pH of a 0.33 M benzoic acid solution if the K, is 6.3x 10-S 12. Calculate the percent error introduced into the reported pH in Question #11 (above assuming the weak acid does not ionize more than 5%? 53 specity whether the aqueous solutions of the following salts are acidic, basic or neutral. NaCO A Fe(N)Explanation / Answer
9.
Since KOH can produce only one hydroxyl ion but Ca(OH)2 can produce two hydroxyl ions, the conentration of OH- ions coming from KOH is less than that of from Ca(OH)2, and hence the pH os KOH is more.
10.
pH = - Log[H+]
4.63 = -Log[H+]
Log[H+] = - 4.63
[H+] = 2.34 * 10-5 M
Accordeint to Ostwald's equation,
[H+] = sqrt.(Ka*C)
2.34 * 10-5 = sqrt.(Ka * 0.22)
5.48 * 10-10 = Ka * 0.22
Ka = 2.49 * 10-9
11.
According to Ostwald's equation,
[H+] = sqrt.(Ka*C)
[H+] = sqrt.(6.3 * 10-5 * 0.33)
[H+] = 4.56 * 10-3 M
Now,
pH = - Log[H+]
pH = - Log(4.56 * 10-3)
pH = 2.34
13.
(a) CaCl2 is the salt obtained by strong base and strong acid and hence is Neutral.
(b) NH4NO3 is obtained by weak base and strong acid, and hence is acidic in nature
(c) Na2CO3 is the salt obtained by strong base and weak acid, and hence is basic in nature.
(d) Fe(NO3)2 is the salt obtained by weak base and strong acid, and hence is acidic in nature.