A 0.870 g sample of a monoprotic acid is dissolved in water and titrated with 0.300 M KOH.
What is the molar mass of the acid if 23.0 mL of the KOH solution is required to neutralize the sample?

The molar mass of monoprotic acid is 126.1 g/mol

Explanation:

To calculate the molarity of solution, we use the equation:

Molarity of KOH solution = 0.300 M

Volume of solution = 23.00 mL

Putting values in above equation, we get:

The chemical equation for the reaction of monoprotic acid and KOH follows:

By Stoichiometry of the reaction:

1 mole of KOH reacts with 1 mole of HA

So, 0.0069 moles of KOH will react with = moles of HA

To calculate the molar mass for given number of moles, we use the equation:

Given mass of HA = 0.870 g

Moles of monoprotic acid = 0.0069 mol

Putting values in above equation, we get:

Hence, the molar mass of monoprotic acid is 126.1 g/mol

pure substance: iron,copper

impure substance: water,charcoal

since the atomic number is the number of protons in the nucleus, as we move to the left on the periodic table, the electrostatic pull between the nucleus and the valence electron shell decreases. as we move down a group (vertical column), the valence shell energy level gets further and further from the nucleus.