Answer: To calculate the molar concentration of H3O+ (hydronium ions) in a solution given its pH, you can use the formula:
pH = -log[H3O+]
where [H3O+] represents the molar concentration of hydronium ions in moles per liter (mol/L).
Given the pH of the cola solution as 2.670, we can plug this value into the equation:
2.670 = -log[H3O+]
To find [H3O+], we need to isolate it on one side of the equation. First, divide both sides by -1:
-2.670 = log[H3O+]
Now, we need to undo the logarithm. Since the pH value represents the negative logarithm, we can use the antilogarithm (10^x) to find [H3O+]:
[H3O+] = 10^(-2.670)
Using a calculator, the molar concentration of H3O+ in the cola solution is approximately 0.002677 mol/L.
So, the molar concentration of H3O+ in the cola is approximately 0.002677 mol/L.