Please Help! Ammonia (NH3, Kb = 1.8 x10-5) and trimethylamine [(CH3)3N, Kb = 7.4 x10-5] are weak bases.

asked by @wendya2 • about 1 year ago • Chemistry • 5 pts

Ammonia (NH3, Kb = 1.8 x10-5) and trimethylamine [(CH3)3N, Kb = 7.4 x10-5] are weak bases. a. Which of these is the stronger base. Explain your reasoning. b. For the stronger base, calculate the pH and percent ionization of a 0.350 M solution.

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1 answer

Hey Wendy!

You just have to look at the Kb values to know the stronger acid. A higher Kb value means that it is a stronger base. So, trimethylamine (CH3)3N will be the stronger base between the two.

The solution for pH and percent ionization is posted below. I hope this helps!

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answered by @leot1 • about 1 year ago
  • Hello @leot1, can you explain why there is OH– wendy commented about 1 year ago
  • Hey Wendy! Because (CH3)3N is a weak base, you react it with water and water will act as an acid, donating one of its H+ to the base. This is why the species on the product side are (CH3)NH+ and OH- . OH- is whats left of water when it donated an H+. Hope that makes sense to you! Dasha commented about 1 year ago
  • Thank you! You made it very clear wendy commented about 1 year ago
  • You're welcome! Dasha commented about 1 year ago