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pH

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sav07:
Hey! The question says:
HA has Ka 1.6 x 10^-5
Calculate the pH of a 0.001 ml L solution of HA
I was just wondering how I can calsulate the pH from the Ka

kauac:

--- Quote from: sav07 on January 23, 2019, 08:04:38 pm ---Hey! The question says:
HA has Ka 1.6 x 10^-5
Calculate the pH of a 0.001 ml L solution of HA
I was just wondering how I can calsulate the pH from the Ka

--- End quote ---

Hi, would you be able to clarify your acronyms? :)

HA = hydrochloric acid?
Ka = ??

sav07:
HA is just an acid it doesn't specify which one, and Ka is the equilibrium constant for the acid dissociation

david.wang28:

--- Quote from: sav07 on January 23, 2019, 08:11:01 pm ---HA is just an acid it doesn't specify which one, and Ka is the equilibrium constant for the acid dissociation

--- End quote ---
Hi Sav! If this is HA, then you would want to write H^+ + A^- as your dissociation reaction. Then you would want to write the Ka reaction (products over reactants). You should find the concentration of HA (c= n/v) and once you have done that, draw up an ICE table (I'm sure you can work this out for yourself). Then, find the concentration of H^+, and sub that number into pH = -log(H^+), and you should get the answer! :)

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