Consider an aqueous solution at $25C$ to which $HCl($hydrochloric acid$)$ is added along with a dose of a strong base. $($The strong base will be used to change the pH$.)$

$($a$)$ What is the $p{K}_a$ of $HCl?$ Is it a strong or weak acid?

$($b$)$ Use the reaction quotient to calculate the ratio of $[$Cl$-]/[$HCL$]$ for pH $=1,$ pH $=4,$ pH $=7,$ pH $=10$

$($c$)$ Again using the reaction quotient, determine the $pH$ at which the ratio of $[$Cl$-]/[$HCL$]=1.$Is this a relevant $pH$ for normal environmental and natural systems?

$($d$)$ Use your answers to parts a$-$c to justify our assumption that strong acids fully dissociate.

Consider an aqueous solution at $25C$ to which to which CH$3$COOH $($acetic acid$)$ is added along with a dose of strong acid or base

$($e$)$ What is the $p{K}_a$ of CH$3$COOH?Is it a strong or weak acid?

$($f$)$ Calculate the ratio of $[$CH$3$COO$-]/[$CH$3$COOH$]$ for pH $=1,$ pH $=4,$ pH $=7,$ pH $=10$