Question

This question has three parts.

A) What is the mass of 12.17 mL of acetic acid (98% wt/wt)?

B) How many mmols of acid are present in the solution?

Also, what does 98% wt/wt mean?

Answer 1

Answer -

Given,

Volume of Acetic Acid = 12.17 mL

(Wt/wt)% = 98 %

Molar Mass of Acetic Acid = 60.052 g/mol

Density of Acetic Acid = 1.049 g/mL

A) Mass of Acetic Acid

We know that,

Density = Mass/Volume

So, mass of Acetic acid = Density * Volume

So, mass of Acetic acid = 1.049 g/mL * 12.17 mL =12.766 g

This is mass of 100% acetic acid

Also,

%(wt/wt) = mass of solute/mass of solution * 100

So, Mass of 98% wt/wt acetic acid is ,

98 = mass of solute/12.766 g * 100

0.98 = mass of solute/12.766 g

mass of solute = 0.98 * 12.766 g

mass of solute = 12.51 g [ANSWER]

B) mmols of acid = ?

We know that,

Moles = Mass /Molar Mass

So, Moles of acid = 12.51 g /60.052 g/mol

Moles of acid = 0.20831 mol

Now,

1 mol = 10³ mmol

So, 0.20831 mol = 208.31 mmol

mmols of acetic acid = 208.31 mmol [ANSWER]

98% wt/wt means 98g of acetic acid in 100g of solution.