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Chemistry Forums for Students => High School Chemistry Forum => Topic started by: Courtney on March 08, 2005, 12:43:25 PM

Title: pH
Post by: Courtney on March 08, 2005, 12:43:25 PM: What is the pH of 0.0180M ammonia?
Title: Re:pH
Post by: Donaldson Tan on March 08, 2005, 02:56:43 PM: use Ka or Kb to solve for the pH for the corresponding equilibrium expression.
Title: Re:pH
Post by: Mitch on March 08, 2005, 07:34:33 PM: Write a chemical equation. ;)
Title: Re:pH
Post by: Borek on March 09, 2005, 06:30:04 PM: Quote from: Courtney on March 08, 2005, 12:43:25 PM
What is the pH of 0.0180M ammonia?

Regardless of what pH is, only 3.1% ammonia is in protonated form. BATE rulez :)
Title: Re:pH
Post by: Donaldson Tan on March 10, 2005, 08:55:54 AM: NH3 + H2O <-> NH4+ + OH-
Kb = [OH-][NH4+]/[NH3]
let x be change in NH3 concentration
[NH3] = 0.018 - x
[NH4+] = x
[OH-] = x

solve for x, then use pH + pOH = 14 to find the required pH
Title: Re:pH
Post by: pizza1512 on March 10, 2005, 09:03:16 AM: How do you work out the pH of anything in chemistry...
Title: Re:pH
Post by: Donaldson Tan on March 10, 2005, 09:40:47 AM: i think the best mean is to use a pH meter to directly measure the pH, instead of us pressing numbers on our calculator. LOL
Title: Re:pH
Post by: Mitch on March 10, 2005, 09:29:10 PM: Quote from: pizza1512 on March 10, 2005, 09:03:16 AM
How do you work out the pH of anything in chemistry...

On paper? Or in practice?
Title: Re:pH
Post by: Borek on March 12, 2005, 06:51:57 PM: Quote from: pizza1512 on March 10, 2005, 09:03:16 AM
How do you work out the pH of anything in chemistry...

Me? I am using BATE :)