A 0.5224g sample of an unknown monoprotic acid was titrated with 0.0998M of NaOH. The equivalence point of the titration occurs at 23.82 mL. Determine the molar mass of the unknown acid.
mols NaOH = M x L = ?
mols HA = mols NaOH (since it's a monoprotic acid)
mols HA = grams HA/molar mass HA
You know mols HA and grams HA, solve for molar mass HA.
0.5224 mol NH4NO3
Why did the acid go to therapy? Because it had some unresolved equilibrium issues with the NaOH! Now, onto your question. To find the molar mass of the unknown acid, we need to use the equation Molar Mass (g/mol) = Mass (g) / Moles.
First, let's find the number of moles of NaOH used at the equivalence point. We'll use the equation Moles = Concentration (M) * Volume (L). With a concentration of 0.0998M and a volume of 23.82mL (convert to L by dividing by 1000), we can calculate the moles of NaOH used.
Next, we use the balanced chemical equation to figure out the ratio between the unknown acid and NaOH. If the unknown acid is monoprotic (meaning it donates one proton per molecule), the balanced equation is:
Unknown Acid + NaOH → NaX + H2O
The ratio is 1:1 between the unknown acid and NaOH, so the moles of NaOH used represents the moles of the unknown acid.
Finally, we can calculate the molar mass of the unknown acid by dividing the mass of the sample (0.5224g) by the number of moles we just found.
I'll let you do the math, because when it comes to numbers, I'm more of a juggler than a mathematician! Just remember to keep your balancing skills sharp and use the correct units.
To determine the molar mass of the unknown acid, we need to calculate the number of moles of the acid present in the 0.5224g sample.
1. Calculate the number of moles of NaOH used in the titration:
Given: Concentration of NaOH = 0.0998 M
Volume of NaOH used = 23.82 mL = 0.02382 L
Moles of NaOH = Concentration of NaOH * Volume of NaOH used
= 0.0998 M * 0.02382 L
≈ 0.002372 mol
2. Since NaOH and the unknown acid react in a 1:1 stoichiometric ratio, the number of moles of the unknown acid is also 0.002372 mol.
3. Calculate the molar mass of the unknown acid:
Given: Mass of the acid sample = 0.5224 g
Moles of the acid = 0.002372 mol
Molar mass of the acid = Mass of the acid sample / Moles of the acid
= 0.5224 g / 0.002372 mol
≈ 220.58 g/mol
Therefore, the molar mass of the unknown acid is approximately 220.58 g/mol.
To determine the molar mass of the unknown acid, we need to follow a series of steps:
Step 1: Calculate the number of moles of NaOH used in the titration.
- Moles of NaOH = (Molarity of NaOH) x (Volume of NaOH used in titration)
- Moles of NaOH = 0.0998 M x 0.02382 L = 0.002376 moles
Step 2: Determine the stoichiometry between NaOH and the unknown acid.
- From the balanced chemical equation, we know that 1 mole of monoprotic acid reacts with 1 mole of NaOH.
Step 3: Calculate the number of moles of the unknown acid.
- Moles of unknown acid = Moles of NaOH used in the titration
- Moles of unknown acid = 0.002376 moles
Step 4: Calculate the molar mass of the unknown acid.
- Molar mass (g/mol) = Mass (g) / Moles
- Molar mass = 0.5224 g / 0.002376 moles = 219.86 g/mol
Therefore, the molar mass of the unknown acid is approximately 219.86 g/mol.