2. Extract the relevant information from the question: NaOH V = 30 mL , M = 0.10 M HCl V = 25.0 mL, M = ?

0.12M

Explanation:

A balanced equation for the reaction will go a great deal in obtaining our desired result. So, let us write a balanced equation for the reaction

HCl + NaOH —> NaCl + H2O

From the above equation,

nA (mole of the acid) = 1

nB (mole of the base) = 1

Data obtained from the question include:

Vb (volume of the base) = 30mL

Mb (Molarity of the base) = 0.1M

Va (volume of the acid) = 25mL

Ma (Molarity of the acid) =?

The molarity of the acid can be obtained as follow:

MaVa/MbVb = nA/nB

Ma x 25/ 0.1 x 30 = 1

Cross multiply to express in linear form

Ma x 25 = 0.1 x 30

Divide both side by 25

Ma = (0.1 x 30) / 25

Ma = 0.12M

The molarity of the acid is 0.12M

a compound is a molecule made of atoms from different elements.

a. by the combination of an unlimited number of elements