The pH of Solutions of Weak Acids and Bases 12.73

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Semi Yoon
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Joined: Fri Sep 28, 2018 12:27 am

The pH of Solutions of Weak Acids and Bases 12.73

Postby Semi Yoon » Sun Jan 20, 2019 10:18 pm

If a 15.5-g sample of CH3NH3Cl is dissolved in water to make 450. mL of solution, how would you find the pH of the solution?

Nahelly Alfaro-2C
Posts: 59
Joined: Wed Nov 15, 2017 3:04 am

Re: The pH of Solutions of Weak Acids and Bases 12.73

Postby Nahelly Alfaro-2C » Sun Jan 20, 2019 10:52 pm

The pH of the solution can be found by first finding the equilibrium the conjugate acid of the weak base and finding its Ka and Kb. From there an ICE table can be created in order to find the concentrations based on the concentrations that were provided by the problem. You could then find the Ka by dividing Kw by Kb. Then, substitute the equilibrium concentrations into the expressions for Ka. Then solve for X and take the pH by taking the log of H3O+ because H3O+ is equal to X.


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