I have an answer key, but I would like to k ow how to actually solve the problem

Question

I have an answer key, but I would like to k ow how to actually solve the problems.

13) What is the pH of a 0.0150 M aqueous solution of barium hydroxide? A) 10.4 B) 1.52 C) 12.2 D) 12.5 14) What is the pH of a 0.0150 M solution of barium hydroxide? A)12.2 B) 10.4 C)1.82 D) 12.5 E)1.52 15) An aqueous solution contains 0.100 M NaOH at 25.0 degree C. The pH of the solution is 16) HZ is a weak acid. An aqueous solution of HZ is prepared by dissolving 0.020 mol of HZ in sufficient water to yield 1.0 L of solution. The pH of the solution was 4.93 at 25.0 degree C. The Ka of HZ is.

Explanation / Answer

pOH = -log [OH-]   

= -log (0.0150)

= 1.82 [answer to 13]

pH = 14 - pOH

= 14 - 1.82

= 12.18 = (12.2) [answer to 14]

15.

pOH = -log [OH-]   

= -log (0.010)

= 2.0

pH = 14 - pOH

= 14 - 2

= 12 [answer]

16. pH = 4.93 = - log [H+]

[H+] = antilog ( - 4.93) = 10-4.93

= 1.17 * 10-5 M

HZ ----------> H+ + Z-

0.020 --- - I

(- 1.17 * 10-5)    1.17 * 10-5    1.17 * 10-5 C

(0.020 - 1.17 * 10-5) 1.17 * 10-5    1.17 * 10-5 E

so Ka = [ 1.17 * 10-5 ] [1.17 * 10-5 ]

(0.020 - 1.17 * 10-5)

Ka = 6.9 * 10-9

Its option D and not B

Related Questions

Navigate

• Browse (All)
• Browse I
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.