There are 3 possible ways of determining pH.
1. A pH meter, 2. Litmus paper/ pH test strips or 3. Titrations.
1. A pH meter works by sending a small electric current through the solution. An electrical current can only be created if there are free-moving particles such as H+ ions from an acid or OH- ions from a base. The pH meter can determine the pH by how high the conductivity is.
2. Litmus Paper or pH test strips are strips that turn a specific colour under a specific pH. This colour can then be compared to a colour chart which will tell you the pH. The downfall of this method is that the red ink will stain the strip and you will be unable to get an accurate reading.
3. A titration is the best method, if done properly, for determining pH.
Answer:
pH = 4.25
Explanation:
A solution composed of a weak acid and its conjugate base is a <em>buffer solution</em>. To calculate the pH of a buffer solution we use the Henderson-Hasselbach equation:
pH = pKa + log ([conjugate base]/[weak acid]
In this case, we have the following data:
[conjugate base] = [sodium benzoate] = 0.230 M
[weak acid] = [benzoic acid] = 0.205 M
The pKa of benzoic acid is 4.2. So, we introduce the data in the equation:
pH = 4.2 + log (0.230 M/0.205 M) = 4.2 + 0.050 = 4.25
Answer:
Condensation
Explanation:
Thermal energy is released in this process