Final answer:
The pH of a stomach acid solution with 0.155 M HCl is approximately 0.81 and the pOH is approximately 13.19.
Step-by-step explanation:
To calculate the pH of a stomach acid solution where the concentration of HCl is 0.155 M, we first acknowledge that HCl is a strong acid and will dissociate completely in water. Therefore, the concentration of hydronium ions [H3O+] is equal to the concentration of HCl, which is 0.155 M. The pH is then found using the formula:
pH = -log[H3O+]
Plugging in the numbers gives us:
pH = -log(0.155) ≈ 0.81
To find the pOH, we use the relationship that at 25 °C, pH + pOH = 14. Thus:
pOH = 14 - pH ≈ 14 - 0.81 ≈ 13.19
Therefore, the pH and pOH of the 0.155 M HCl solution, representing stomach acid, are approximately 0.81 and 13.19, respectively.