Answer:
0.134M
Explanation:
First, we begin by writing a balanced equation for the reaction. This is illustrated below:
2HNO3 + Ca(OH)2 —> Ca(NO3)2 + 2H2O
From the equation:
nA (mole of the acid) = 2
nB (mole of the base) = 1
Data obtained from the question include:
Ma (Molarity of acid) =?
Va (volume of acid) = 20.7 mL
Mb (Molarity of base) = 0.106 M
Vb (volume of base) = 13.1 mL
Using MaVa/MbVb = nA/nB, we can calculate the molarity of the acid as follow:
MaVa/MbVb = nA/nB
Ma x 20.7/ 0.106 x 13.1 = 2/1
Cross multiply to express in linear form as shown below:
Ma x 20.7 = 0.106 x 13.1 x 2
Divide both side by 20.7
Ma = (0.106 x 13.1 x 2) / 20.7
Ma = 0.134M
Therefore, the molarity of the acid is 0.134M
