Ascorbic acid (vitamin C) is a diprotic acid having the formula H2C6H6O6. A sample of a vitamin supplement was analyzed by titrating a 0.3252 g sample dissolved in water with 0.0284 M NaOH. A volume of 13.27 mL of the base was required to completely neutralize the ascorbic acid. What was the percentage by mass of ascorbic acid in the sample?

mols NaOH = M x L = ?

1 mol NaOH = 2 mol ascorbic acid
g ascorbic acid = mols x molar mass
%asc = (g asc/mass sample)*100 = ?

Why did the ascorbic acid go to school?

To get titrated!

Now, let's solve this problem step by step.

Step 1: Calculate the number of moles of NaOH used in the titration.

Number of moles of NaOH = concentration x volume
= 0.0284 M x 0.01327 L

Step 2: Determine the number of moles of ascorbic acid that reacted.

Since ascorbic acid is diprotic, we need to find the moles of NaOH reacted per mole of ascorbic acid. The balanced chemical equation is:

2 NaOH + H2C6H6O6 -> Na2C6H6O6 + 2 H2O

From the balanced equation, we see that 2 moles of NaOH react with 1 mole of ascorbic acid.

So, number of moles of ascorbic acid = 0.5 x number of moles of NaOH

Step 3: Calculate the molar mass of ascorbic acid (H2C6H6O6).

Molar mass = (2 x atomic mass of H) + (6 x atomic mass of C) + (6 x atomic mass of O)
= (2 x 1.008) + (6 x 12.01) + (6 x 16.00)

Step 4: Calculate the mass of ascorbic acid in the sample.

Mass of ascorbic acid = number of moles x molar mass

Step 5: Calculate the percentage by mass of ascorbic acid in the sample.

Percentage by mass = (mass of ascorbic acid / mass of sample) x 100

Now, go ahead and put those numbers in and calculate the answer!

To find the percentage by mass of ascorbic acid in the sample, you'll need to determine the amount of ascorbic acid in the 0.3252 g sample, and then calculate the percentage.

Step 1: Calculate the moles of NaOH used in the titration.
Since the volume of NaOH used is 13.27 mL and its molarity is 0.0284 M, you can calculate the moles of NaOH using the formula:
moles of NaOH = volume (in L) × molarity
moles of NaOH = 13.27 mL × 0.0284 M / 1000 mL/L

Step 2: Calculate the moles of ascorbic acid.
Ascorbic acid is a diprotic acid, meaning it can donate 2 protons (H+) per molecule. So each mole of ascorbic acid will react with 2 moles of NaOH.
moles of ascorbic acid = (moles of NaOH) / 2

Step 3: Calculate the molar mass of ascorbic acid.
The molar mass of ascorbic acid (H2C6H6O6) can be calculated by adding up the atomic masses of its elements.

Step 4: Calculate the mass of ascorbic acid.
mass of ascorbic acid = (moles of ascorbic acid) × (molar mass of ascorbic acid)

Step 5: Calculate the percentage by mass.
percentage by mass = (mass of ascorbic acid / mass of sample) × 100

By following these steps, you should be able to find the percentage by mass of ascorbic acid in the sample.

To find the percentage by mass of ascorbic acid in the sample, we need to determine how many moles of ascorbic acid were present in the 0.3252 g sample. Then, we can calculate the molar mass of ascorbic acid to find the percentage.

First, let's find the number of moles of NaOH used in the titration:

Moles of NaOH = Molarity of NaOH * Volume of NaOH (in liters)

Molarity of NaOH = 0.0284 M (given)
Volume of NaOH = 13.27 mL = 0.01327 L

Moles of NaOH = 0.0284 M * 0.01327 L = 0.000376068 moles

Since NaOH and ascorbic acid have a 1:1 stoichiometric ratio in the balanced equation, the moles of NaOH used is equal to the moles of ascorbic acid in the sample.

Next, let's calculate the molar mass of ascorbic acid:

Molar mass of ascorbic acid (H2C6H6O6) =
(2 * atomic mass of H) + (6 * atomic mass of C) + (6 * atomic mass of H) + (6 * atomic mass of O)

Atomic mass of H = 1.00784 g/mol
Atomic mass of C = 12.011 g/mol
Atomic mass of O = 15.999 g/mol

Molar mass of ascorbic acid = (2 * 1.00784) + (6 * 12.011) + (6 * 1.00784) + (6 * 15.999)
= 176.12448 g/mol

Now, let's calculate the mass of ascorbic acid in the sample:

Mass of ascorbic acid = Moles of ascorbic acid * Molar mass of ascorbic acid
= 0.000376068 moles * 176.12448 g/mol
= 0.06625 g

Finally, let's calculate the percentage by mass of ascorbic acid in the sample:

Percentage by mass = (Mass of ascorbic acid / Mass of sample) * 100
= (0.06625 g / 0.3252 g) * 100
= 20.3795%

Therefore, the percentage by mass of ascorbic acid in the sample is approximately 20.38%.