Answer:
(a) [tex]pH=1[/tex]
(b) [tex]pH=1.3[/tex]
(c) [tex]pH=13[/tex]
(d) [tex]pH=12.7[/tex]
Explanation:
Hello,
In this case, we define the pH in terms of the concentration of hydronium ions as:
[tex]pH=-log([H^+])[/tex]
Which is directly computed for the strong hydrochloric acid (consider a complete dissociation which means the concentration of hydronium equals the concentration of acid) in (a) and (c) as shown below:
(a)
[tex][H^+]=[HCl]=0.1M[/tex]
[tex]pH=-log(0.1)=1[/tex]
(b)
[tex][H^+]=[HCl]=0.05M[/tex]
[tex]pH=-log(0.05)=1.3[/tex]
Nevertheless, for the strong sodium hydroxide, we don't directly compute the pH but the pOH since the concentration of base equals the concentration hydroxyl in the solution:
[tex][OH^-]=[NaOH][/tex]
[tex]pOH=-log([OH^-])[/tex]
[tex]pH=14-pOH[/tex]
Thus, we have:
(b)
[tex]pOH=-log(0.1)=1\\pH=14-1=13[/tex]
(d)
[tex]pOH=-log(0.05)=1.3\\pH=14-1.3=12.7[/tex]
Best regards.