Calculation of pH in strong acid solutions

Calculations of pH values in solutions are closely connected with the equilibrium considerations described in the previous chapter. As it is the case when equilibrium is considered one has to focus on components of the solution and its chemistry. This will be further looked into in the following example  

Example 5- A pH calculation in a strong acid (hydrochloric acid)  

A solution consists of 0.5 M HCL. We know that HCl is a strong acid which is why it is reasonable to assume that the acid is completely dissociated meaning that the following reaction is completely turned to the right  

We neglect as it is often the case the contribution to the concentration of water and assume that all HCl molecules are dissociated which is why from autoprotolysis of 

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