#3 R&D Exp. 26 Should Cu(OH)2 precipitate in 3 M NH3 if the original [Cu2+] is 0.1...

Free

50.1K

Verified Solution

Question

Chemistry

#3 R&D Exp. 26
Should Cu(OH)₂ precipitate in 3 M NH₃ ifthe original [Cu²⁺] is 0.1 M ( the K_b forammonia is 1.6x10^-5)?
Please show work and explain a little of how you got thisresult

Answer & Explanation Solved by verified expert

4.2 Ratings (680 Votes)

In the above problem volumes are not mentioned, so we will consider that volume will remian almost constant even after mixing the two.

Now

Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â NH3 + H2O --> NH4+ + OH-
initialÂ Â Â Â Â Â Â Â Â Â Â Â 3MÂ Â Â Â Â Â Â Â Â Â Â Â Â Â 0Â Â Â Â Â Â Â Â Â Â Â 0

equilibriumÂ Â Â Â Â 3-xÂ Â Â Â Â Â Â Â Â Â Â xÂ Â Â Â Â Â Â Â Â Â Â Â x
Kb = [NH4][OH-]/[NH3] = 1.6X10^-5 = [x][x]/[3-x]

Its a weak base so x<<1

1.6X10^-5 = x^2 / 3

x^2 = 48X10^-6

x = 6.92X10^-3 = [OH-]

Now Ksp of copper hydroxide is

Cu(OH)2 <-----> Cu2+ + 2OH- Ksp = 4.8X10^-20

And Ionic product = [Cu+2][OH-] = 0.1 X 6.92X10^-3 = 6.92X10^-4

IP >>Ksp

so precipitate will form

Get Answers to Unlimited Questions

Join us to gain access to millions of questions and expert answers. Enjoy exclusive benefits tailored just for you!

Membership Benefits:

Unlimited Question Access with detailed Answers
Zin AI - 3 Million Words
10 Dall-E 3 Images
20 Plot Generations
Conversation with Dialogue Memory
No Ads, Ever!
Access to Our Best AI Platform: Flex AI - Your personal assistant for all your inquiries!

Become a Member