What mass of benzoic acid can be made from a reaction where 4.87g benzyl alcohol is combined with 300mL of bleach? The reaction is conducted in water and dichloromethane. Describe a method of separating the benzoic acid from the sodium chloride byproduct after the reaction is complete.

Write the equation and balance it.

Convert 4.87 benzyl alcohol to moles. moles = grams/molar mass.
Using the coefficients in the balanced equation (I think it is 1:1 but you can tell from the balanced equation you wrote), convert moles benzyl alcohol to moles of the product, benzoic acid.
Now convert moles benzoic acid to grams benzoic acid. grams = moles x molar mass.
To separate the product, look at the solubilities of benzyl alcohol and benzoic acid in water and in dichloromethane.
If you treat the finished solution with NaHCO3, that will convert the acid to the sodium salt which will be soluble in water. You can then pour into a sep funnel and separate the organic phase from the water phase. I would wash two or three times to make sure I obtained all of the product. Then the aq phase can be acidified which will return the sodium benzoate to benzoic acid and extract with an organic phase, wash, dry, and evaporate the solvent.

Thank you Chad for asking this question and thank you Br. Bob for answering it!

To determine the mass of benzoic acid produced, we need to set up a balanced chemical equation for the reaction between benzyl alcohol and bleach. However, the equation provided is incomplete because it doesn't mention the specific reactants and conditions. Therefore, I'll assume a plausible equation:

C6H5CH2OH (benzyl alcohol) + NaOCl (bleach) → C6H5COOH (benzoic acid) + NaCl (sodium chloride) + H2O (water)

To calculate the mass of benzoic acid produced, we need to follow these steps:

Step 1: Convert the volume of bleach from milliliters to grams.
To do this, we'll need to know the density of bleach. Since the density is not provided, we'll assume the density of bleach is close to that of water, which is 1 g/mL.

Mass of bleach = Volume of bleach × Density of bleach
Mass of bleach = 300 mL × 1 g/mL
Mass of bleach = 300 g

Step 2: Determine the limiting reagent.
To determine the limiting reagent, we need to compare the number of moles of benzyl alcohol and bleach used. From the given values, we know the mass of benzyl alcohol is 4.87 g. To find the number of moles, we'll divide the mass by the molar mass.

Molar mass of benzyl alcohol (C6H5CH2OH) = (6 × 12.01 g/mol) + (6 × 1.008 g/mol) + 12.01 g/mol + 16.00 g/mol + 1.008 g/mol = 108.14 g/mol

Number of moles of benzyl alcohol = Mass of benzyl alcohol / Molar mass = 4.87 g / 108.14 g/mol ≈ 0.045 moles

From the balanced equation, we can see that the mole ratio between benzyl alcohol and benzoic acid is 1:1. Therefore, the number of moles of benzoic acid produced is also 0.045 moles.

Next, we'll calculate the number of moles of sodium hypochlorite (bleach) used. Since the molar ratio between bleach and benzoic acid is 1:1 in the balanced equation, the number of moles of bleach used will also be 0.045 moles.

Since the number of moles of both reactants is equal, neither is in excess, and they fully react with each other. Therefore, there is no limiting reagent in this scenario.

Step 3: Calculate the mass of benzoic acid produced.
To find the mass of benzoic acid, we'll use the same formula as before:

Mass of benzoic acid = Number of moles × Molar mass
Mass of benzoic acid = 0.045 moles × 122.12 g/mol (molar mass of benzoic acid)
Mass of benzoic acid ≈ 5.50 g

Therefore, approximately 5.50 grams of benzoic acid can be produced from the given reaction.

Now, to describe a method for separating the benzoic acid from the sodium chloride byproduct:

1. Dissolve the reaction mixture in a suitable solvent: Since benzoic acid is not very soluble in water, and sodium chloride is highly soluble, we can dissolve the reaction mixture in a solvent such as dichloromethane (also known as methylene chloride). This solvent will selectively dissolve the benzoic acid while leaving the sodium chloride behind.

2. Separate the organic and aqueous layers: After thoroughly mixing the dichloromethane and water layers, allow them to separate into two distinct layers based on their density. The denser aqueous layer will contain the sodium chloride, while the less dense organic layer will contain the dissolved benzoic acid.

3. Extract the benzoic acid: Carefully separate the organic layer (containing the benzoic acid) from the aqueous layer. Collect the organic layer in a clean container.

4. Wash the organic layer: To remove any remaining impurities, wash the organic layer (containing the benzoic acid) with a small amount of water. This helps remove traces of sodium chloride and other water-soluble impurities.

5. Evaporate the solvent: Transfer the washed organic layer to an evaporating dish or container and evaporate the dichloromethane solvent using gentle heat or by allowing it to evaporate naturally. This will leave behind the solid benzoic acid.

6. Collect the benzoic acid: Once the solvent has completely evaporated, you'll be left with solid benzoic acid in the evaporating dish. Carefully collect it using a spatula or scrape it off the dish's surface.

By following these steps, you can separate the benzoic acid from the sodium chloride byproduct after the reaction is complete.