Answer:
a. 87.8g/mol is the molar mass of the acid.
b. The answer is in the explanation.
Explanation:
To solve this question we must find the moles of the monoprotic acid using the reaction with NaOH (1mole of monoprotic acid reacts with 1 mole of NaOH). With the moles and the mass of the unknown we can find the molar mass.
Moles of NaOH added:
0.04121L * (0.150moles / L) = 6.1815x10⁻³ moles NaOH = Moles monoprotic acid
Molar mass is:
0.543g / 6.1815x10⁻³ moles = 87.8g/mol is the molar mass of the acid
b. I can't see the image you are giving because has a low resolution. But the identity of the acid can be obtained because the acid:
Has the same molar mass.
Is a monoprotic acid.
(a) The molecular mass of the unknown monoprotic acid will be 87.84 g/moles.
(b) The acid can be butyric acid, as it is a monoprotic and have mass near about 87.84 g/mol.
(a) The endpoint by the addition of NaOH has been reached when the monoprotic acid has been completely utilized. Since the NaOH has been monobasic. The moles of NaOH will be equal to the moles of acid.
Moles of NaOH = moles of acid
The molarity of NaOH = 0.15 M
Volume of NaOH = 41.21 ml
Molarity = [tex]\rm \dfrac{moles}{volume\;(L)}[/tex]
Moles = molarity [tex]\times[/tex] volume (L)
Moles of NaOH = 0.15 [tex]\times[/tex] 0.04121 L
Moles of NaOH = 0.00618 moles
Moles of NaOH = moles of acid
moles of acid = 0.00618 moles.
Mass of acid dissolved = 0.543 grams
Molecular weight of acid = [tex]\rm \dfrac{weight}{moles}[/tex]
Molecular weight of acid = [tex]\rm \dfrac{0.543}{0.006815}[/tex]
Molecular weight of acid = 87.84 g/moles.
(b) The acid with the molecular mass of 87.84 g/mol with being the monoprotic acid can be butyric acid. The butyric acid has a molecular weight of 88 g/mol.
For more information about monoprotic acid, refer to the link:
https://brainly.com/question/22497931
