Question

1. What volume of toluene do you need to add to 1 mL of ethyl acetate to make an equi-molar mixture? The density of ethyl acetate (C4H8O2) is 0.898 g/mL and the density of toluene (C7H8) is 0.867 g/mL.

Answer 1

Answer:

1.06 mL of toluene will be needed.

Explanation:

Equi-molar mixture means equal moles of all the components.

as given the volume of ethyl acetate = 1mL

Density of ethyl acetate = 0.898 g/mL

The relation between density, mass and volume is :

$density=\frac{mass}{volume}$

mass=volumeXdensity

mass of ethyl acetate present = 1mL X 0.898g/mL = 0.598 grams

the moles are related to mass as:

$moles=\frac{mass}{molarmass}$

For ethyl acetate molar mass = 4X12+8X1+2X16= 88g/mol

moles of ethyl acetate will be:

$moles=\frac{0.898}{88}= 0.01mol$

So we need 0.01 moles of toluene also

For 0.01 moles the mass of toluene required = 0.01 X molar mass of toluene

mass required = 0.01 X 92=0.92grams

for 0.92 grams of toluene volume required will be:

$volume=\frac{mass}{density}=\frac{0.92}{0.867}= 1.06mL$