How do I find the pH of pure neutral H2O at o degrees celsius by using standard enthalpies and standard entropies
To find the pH of pure neutral H2O at 0 degrees Celsius using standard enthalpies and standard entropies, we need to make use of the concept of water dissociation or self-ionization.
1. Start by writing the balanced chemical equation for the self-ionization of water:
H2O(l) ↔ H+(aq) + OH-(aq)
2. The pH of a solution is given by the formula:
pH = -log[H+]
3. The concentration of H+ in pure neutral water is equal to the concentration of OH-. This means that [H+] = [OH-]. So, we can substitute [OH-] for [H+] in the formula.
4. Since we are dealing with pure neutral water, the concentrations of H+ and OH- are both 1 × 10^-7 M at 0 degrees Celsius.
Now, let's calculate the pH.
pH = -log[H+]
= -log[OH-]
= -log(1 × 10^-7)
= -(-7)
= 7
Therefore, the pH of pure neutral H2O at 0 degrees Celsius, when using standard enthalpies and standard entropies, is 7.