Q. 10.63 - An Introduction to General, Organic, and Biological Chemistry

Question

At rest, the $\left[{\mathrm{H}}_3{\mathrm{O}}^{+}\right]$of the stomach fluid is $2.0\times {10}^{-4}\mathrm{M}$. What is the $\mathrm{pH}$ of the stomach fluid?

Step-by-Step Solution

Answer

The  pH  text of the stomach  fluid  is  3.70.

Step - 1 Introduction

The solution's $\mathrm{pH}$ can be defined as the negative logarithmic (base 10) of the $\left[{\mathrm{H}}_3{\mathrm{O}}^{+}\right]$  concentration .

$\mathrm{pH}=-\log \left[{\mathrm{H}}_3{\mathrm{O}}^{+}\right]$

$\mathrm{pOH}=-\log \left[{\mathrm{OH}}^{-}\right]$

$\mathrm{pH}+\mathrm{pOH}=14$

Step - 2 Explanation

The solution has an acid concentration of $2.0\times {10}^{-4}\mathrm{M}$. Calculate the solution's $\mathrm{pH}$ using the following formula:

$pH=-\log \left[{\mathrm{H}}_3{\mathrm{O}}^{*}\right]$

     $=-\log \left[2.0\times {10}^{-4}\right]$

     $=4-\log (2.0)$

     $=3.70$

As a result, the pH text of the stomach fluid is 3.70.