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    Calculating pH

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    1) Calculate the pH of the following solutions:
    (a) 0.010 M acetic acid (Ka= 1.76E-5)

    CH3COOH + H2O --> H3O+ + CH3COO-
    initial 0.010 -- ? ?
    Equilibrium 0.010-x -- ? ?

    Show how did you solve this equation to get 1.76E-5:

    Ka = [H3O][CH3COO]/[CH3COOH] = 1.76E-5

    (b) 0.010 M hydrochloric acid
    (c) Which acid solution in Question#1(a) or #1(b) has the lower pH ?
    (d) Why does the acid solution noted in (c) have a lower pH ?

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    https://brainmass.com/chemistry/acids-and-bases/calculating-ph-10523

    Solution Preview

    a) If the initial conc. of a weak acid is C moles/litre and if x is the degree of dissociation (defined as the fraction of the total electrolyte split up at equilibrium), then, the equilibrium concentrations would be,
    <br>
    <br>C (1-x) mole/litre, of the undissociated acid and Cx moles/litre each of H+ and A-
    <br>
    <br>the equilibrium constant for the ionization process is given ...

    Solution Summary

    The expert calculates the pH.

    $2.19