Answer:
1.22
Step-by-step explanation:
Step 1:
We'll begin by writing the balanced equation for the reaction. This is given below:
HCl + KOH —> KCl + H2O
From the balanced equation above,
The mole ratio of acid (nA) = 1
The mole ratio of base (nB) = 1
Step 2:
Data obtained from the question. This includes the following:
Volume of acid (Va) =
(62.35 + 62.40)/2 = 62.38 mL
Molarity of acid (Ma) =.?
Volume of base (Vb) = 25 mL
Molarity of base (Mb) = 0.150M
Step 3:
Determination of the molarity of the acid.
This is illustrated below:
MaVa/MbVb = nA/nB
Ma x 62.38/ 0.15 x 25 = 1
Cross multiply to express in linear form
Ma x 62.38 = 0.15 x 25
Divide both side by 62.38
Ma = (0.15 x 25) /62.38
Ma = 0.06M
The molarity of the acid is 0.06M
Step 4:
Determination of the concentration of Hydrogen ion, [H+] in the acid. This is illustrated below:
Hydrochloric acid (HCl) will dissociate to produce hydrogen ion as follow:
HCl —> H+ + Cl-
From the above equation,
1 mole of HCl produced 1mole of H+.
Therefore, 0.06M HCl will also produce 0.06M H+.
The concentration of Hydrogen ion, [H+] is 0.06M
Step 5:
Determination of the pH of HCl. This is illustrated below:
pH = – Log [H+]
[H+] = 0.06M
pH = – Log 0.06
pH = 1.22
Therefore, the pH of HCl is 1.22