Question

What is the pH of human urine if proton concentration is 6.3 x 10^-7 M?

Please show all work and explain your responses.

Answer 1

pH can be defined as the negative logarithm of proton concentration in a medium. The formula for pH is given as :

pH = - log₁₀ [H⁺]

In the above question, the proton concentration of urine is given as 6.3 x 10^-7 M. So we calculate pH using the above formula :

pH = - log₁₀ [H⁺]

= - log₁₀[ 6.3 x 10^-7]

= - log₁₀ 6.3 + - log₁₀ 10^-7

= - 0.799 + 7 log₁₀ 10

= - 0.799 + 7

= 6.201 or 6.2

Thus the pH of urine at a proton concentration of 6.3 x 10^-7 M is 6.2. A pH value below 7 is considered as acidic. Thus the urine is acidic in nature.

PS - The log value of log₁₀ 6.3 was calculated using log table. We know that the value of log₁₀ 10 = 1.