Homework Answers
18) The pH is calculated:
pK = - log Ka + log [NaCl] / [HOCl] = - log 3.2x10 ^ -8 + log (0.05 / 0.41) = 6.58
19) The reaction of a weak acid and a weak base is d.
51) The concentration of the second ion in solution is equal to Ka2 = 6.1x10 ^ -5
52) The pOH and [OH-] are calculated:
pOH = 14 - 10.5 = 3.5
[OH-] = 10 ^ -3.5 = 3.2x10 ^ -4
You have Kb:
Kb = Kw / Ka = 10 ^ -14 / 4.9x10 ^ -10 = 2x10-5
The expression of Kb has:
Kb = [OH-] * [HCN] / [CN-]
2x10 ^ -5 = (3.2x10 ^ -4) ^ 2 / [CN-]
It clears [CN-] = 0.005 M
The mass of NaCN is calculated:
m NaCN = M * V * MM = 0.005 M * 0.25 L * 49 g / mol = 0.059 g
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all please. its okah if its just the answers 14x3/2 +246 €61) S.56 xoto 10. What...
all
please. its okah if its just the answers
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please help!! calculate pH of solutions on second page a-c!!
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please explain how you got all your answers
10. Calculate the pH of a 0.30 M formic acid solution. (K-1.8 x 10") Weak monoprotic acid. 11. Calculate the K, for a 0.050 M solution of HA (weak acid) if the pH = 4.65. 12. What is the pH of the solution which results from mixing 50.0 mL of 0.30 M HF(aq) and 50.0 mL of 0.30 M NaOH(aq) at 25C? (K. of F = 1.4 x 10) 13. Which of...
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all
please. its okah if its just the answers
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