Question

Using the data in the Reagents and Properties table below, please calculate the theoretical yield of

methoxybenzaldehyde in grams, assuming you start with 1.50 g of the alcohol. (Assume the
alcohol is the limiting reactant). Please, show your work.
substance quantity molar mass (g/mole) bp (°C)
bleach (NaOCl) 20 mL
dichloromethane 18 mL 84.93 40°C
ethyl acetate 40 mL 88.11 76—77°C
magnesium sulfate,
anhydrous 1 g 120.37
methoxybenzaldehyde
(reaction product) 136.15 248°C
p-methoxybenzyl alcohol 1.5 g 138.15
sodium chloride,
saturated solution 20—30 mL
sodium hydroxide,5% 20 mL
tetrabutylammonium
hydrogen sulfate 0.15—0.2 g 339.54

Answer 1

The theoretical yield of methoxybenzaldehyde from 1.50 g of p-methoxybenzyl alcohol is 1.48 g, calculated by first converting the mass of the alcohol to moles, then using the stoichiometry of the reaction to find the moles of product, and finally converting these moles back to grams.

Step-by-step explanation:

To calculate the theoretical yield of methoxybenzaldehyde, we will follow these steps:

1. Convert the mass of p-methoxybenzyl alcohol to moles using its molar mass.
2. Use the stoichiometry of the reaction, which is presumed to have a 1:1 mole ratio, to find the moles of methoxybenzaldehyde produced.
3. Convert the moles of methoxybenzaldehyde to grams using its molar mass to find the theoretical yield.

Let's perform the calculations:

1. Calculate moles of p-methoxybenzyl alcohol:

1.50 g p-methoxybenzyl alcohol x (1 mol / 138.15 g) = 0.01086 mol p-methoxybenzyl alcohol

2. Using the 1:1 mole ratio:

0.01086 mol p-methoxybenzyl alcohol produces 0.01086 mol methoxybenzaldehyde

3. Calculate mass of methoxybenzaldehyde:

0.01086 mol methoxybenzaldehyde x (136.15 g / 1 mol) = 1.48 g methoxybenzaldehyde

So, the theoretical yield of methoxybenzaldehyde from 1.50 g of p-methoxybenzyl alcohol is 1.48 g.