Questions: In chemistry, pH=-log [H+]. Given that C is the original concentration of hydrogen ions in a liquid, and P is the original pH of the liquid, P=-log(C). What is the effect on pH if the concentration of hydrogen ions is increased by a factor of 5? The pH decreased by increased by by Question Help: Message instructor Submit Question Jump to Answer

Solution Steps

The pH of a solution is defined by the formula: \[ pH = -\log [H^+] \] where \([H^+]\) is the concentration of hydrogen ions in the solution.

If the original concentration of hydrogen ions is \(C\), and it is increased by a factor of 5, the new concentration becomes: \[ [H^+]_{\text{new}} = 5C \]

Using the formula for pH, the new pH is: \[ pH_{\text{new}} = -\log (5C) \]

Using the properties of logarithms, we can simplify: \[ pH_{\text{new}} = -\log (5) - \log (C) \] Since the original pH, \(P\), is given by \(P = -\log (C)\), we substitute: \[ pH_{\text{new}} = -\log (5) + P \]

The change in pH, \(\Delta pH\), is the difference between the new pH and the original pH: \[ \Delta pH = pH_{\text{new}} - P = -\log (5) \]

Calculate \(-\log (5)\) using a calculator: \[ -\log (5) \approx -0.69897 \]

Final Answer