How to Estimate the pH of a Solution – Part 3

pH is a logarithmic scale used to specify the acidity or basicity of aqueous solutions.


Acidic solutions (with higher concentrations of hydrogen (H+) cations) are measured to have lower pH values than basic or alkaline solutions. The neutral pH is 7. A 𝑝𝐻 meter may be used for a precise and accurate measurement of the 𝑝𝐻 of a solution.

When two or more solutions are mixed, one must add the volumes of all solutions.

Question:

A sample of 200 mL of 0.20 M Sr(OH)2 is added to 800 mL of 0.80 M Ba(OH)2. What is the value that best approximates the pH of the final solution?

Solution:



Click/tap to enlarge the image

NOTE: A strong base is completely ionized; and therefore, the molar concentration is equal to the [OH─].

Want to estimate the pH of a very dilute solution of an acid? Click HERE.

Want to estimate the pH of a weak base? Click HERE.

Striking stoichiometry❓ Let Chemaficionado know in the comments below or at mychemistryhomework@gmail.com❗

Reference:

‌Brown, C.; Ford, M. Higher Level Chemistry, 2nd ed.; Pearson Education: Harlow, Essex, 2014.

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