If 20mL of a 0.100 M NaOH solution are required to titrate 0.25 grams of an unknown acid, what is the equivalent mass of the acid? If the acid actually contains 3 moles of H+ per mole of acid what is the molecular mass of the acid?

mL x N x mew = grams.

20 x 0.1 x mew = 0.25
Solve for milliequivalent weight.

Then equivalent weight = 1000 x mew.
(molar mass/3) = equivalent weight. Solve for molar mass

ялРВ

To find the equivalent mass of the acid, we can use the equation:

Equivalent mass = mass of the acid / volume of solution used for titration

First, we need to convert the given mass of the acid into moles. To do this, we divide the mass by the molar mass of the acid:

Molar mass = mass of the acid / moles of the acid

Since it is mentioned that the acid contains 3 moles of H+ per mole of acid, we can assume that the molar mass refers to the molecular mass of the acid.

To find the molar mass of the acid, we need to know the moles of the acid involved in the reaction with NaOH. From the balanced chemical equation between NaOH and the acid, we can determine the stoichiometric ratio.

Since 20 mL of 0.100 M NaOH solution is required to titrate the acid, we can calculate the moles of NaOH used:

Moles of NaOH = volume of NaOH solution (in L) x molarity of NaOH

First, we convert the volume of NaOH solution from mL to L:

Volume of NaOH solution = 20 mL / 1000 mL/L = 0.02 L

Now, we can calculate the moles of NaOH:

Moles of NaOH = 0.02 L x 0.100 mol/L = 0.002 mol

According to the balanced equation between NaOH and the acid, the stoichiometric ratio is 1:1. This means that 0.002 moles of NaOH react with 0.002 moles of the acid.

Now, we can find the equivalent mass of the acid by using the equation mentioned earlier:

Equivalent mass = mass of the acid / volume of solution used for titration
= 0.25 g / 0.002 L = 125 g/L

Therefore, the equivalent mass of the acid is 125 g/L.

Since the molar mass and the equivalent mass are equal for a substance that donates 1 mole of protons (H+) per mole of substance, the molecular mass of the acid is 125 g/mol.