What is the pH of a #4*10^-2# #M# #HCl# solution?

1 Answer
Apr 27, 2016

Answer:

#pH# #=# #-log_(10)[H_3O^+]# #=# #-log_(10)(4.0xx10^-2)# #=# #1.40#

Explanation:

#pH# #=# #-log_(10)[H_3O^+]# #=# #-log_(10)(4.0xx10^-2)#

We assume (reasonably) that hydrochloric acid will undergo complete dissociation in water to give stoichiometric #H_3O^+# ion, according to the given reaction:

#HCl(aq) + H_2O(l) rarr H_3O^(+) + Cl^-#