Hey guys! Can you please explain each step to the questions that you answer? I a

Question

Hey guys! Can you please explain each step to the questions that you answer? I am having a little trouble with these questions and having a step by step explanation to the answers and how you got them would REALLY help me out. Also if possible, please write neatly :) I appreciate you guys so much. Thanks for all the hard work you guys put in.

9) A 100.0 mL sample of 0.10 M NH3 is titrated with 0.10 M HNO3. Determine the pH of the solution after the addition of 50.0 mL of HNO3, The Kb of NH3 is 1 .8 × 10-5. 10) Determine the molar solubility of AgBr in a solution containing 0.150 M NaBr. Ksp (AgBr) : :XX> 10-13 11) Determine the molar solubility of PbS04 in pure water. Ksp (PbsO4-1.82 x 10-8. 12) Determine the molar solubility of Fe(OH)2 in pure water. Ksp for Fe(OH)2= 4.87 x 10-17 Sp (Al(OH)3) 1.3 x 10-33

Explanation / Answer

9)
moles of NH3 initially present = M*V
= 0.10 M * 0.100 L
= 0.01 mol

moles of HNO3 added = M*V
= 0.10 M * 0.050 L
= 0.005 mol

0.005 mol of both will react to form 0.005 mol of NH4+
mol of NH3 remaining = 0.01 - 0.005 = 0.005 mol

pKb = -log Kb
= -log (1.8*10^-5)
= 4.745

use:
pOH = pKb + log {[NH4+]/[NH3]}
since volume is same for NH4+ and NH3

pOH = pKb + log {n(NH4+)/n(NH3)}
poH = 4.745 + log (0.005/0.005)
poH = 4.745 + log (1)
poH = 4.745 + 0
= 4.745

pH = 14 - pOH
= 14 - 4.745
= 9.255
Answer: 9.255

I am allowed to answer only 1 question at a time

Related Questions

Navigate

• Browse (All)
• Browse H
• Subjects

---