Final answer:
The molar concentration of [H3O+] in a cola with a pH of 3.120 is approximately 7.92 x 10^(-4) M.
Step-by-step explanation:
The molar concentration of [H3O+] in a cola with a pH of 3.120 can be determined using the equation:
pH = -log[H3O+]
First, we need to convert the pH to a hydronium ion concentration. Using the given pH of 3.120, we can rearrange the equation and solve for [H3O+]:
[H3O+] = 10^(-pH)
Plugging in the pH value, we get:
[H3O+] = 10^(-3.120)
Calculating this, we find that the molar concentration of [H3O+] in the cola is approximately 7.92 x 10^(-4) M.