Separating oil from food.

The video on the right shows oil that came from a given mass of a popular brand of blue berry muffin. Oil was isolated following the procedure given below.
   
The image on the right shows some of the apparatus used to separate the oil from the muffin.
   
An evaporating dish was placed on an electronic balance and its mass recorded.
   
A small piece of the muffin was placed in the evaporating, reweighed and the mass of muffin and evaporating dish recorded.
   
20 mL of acetone was measured using a 50 mL measuring cylinder and poured into the evaporating dish with the muffin.
   
A glass rod was used to break up the muffin and mix it thoroughly with the acetone.

 
The contents of the evaporating dish were filtered using filter paper and a100 mL beaker. The filtrate was collected in the 100mL beaker while the residue left behind in the filter paper was washed with a further 20 mL of acetone collected in the same 100mL beaker.
   

The evaporating dish is then wash and thoroughly dried.

The filtrate is then poured into the evaporating dish and allowed to evaporate overnight in a well ventilated fume cupboard.

   
The mass of the oil present in the filtrate and the evaporating dish are weighed and the mass recorded.
   

1. Identify the :

- Filtrate         _______________

- Residue       ______________

- Solvent used ______________

2. Calculate the percent, by mass, of oil in the muffin.
i.       Construct a table of data.
ii.      Show all calculations

3. Consider the image on the right. It is a pre-packaged muffin sold at a convenience store similar to the one tested. Calculate the mass, in grams, of oil present in one whole muffin, as shown on the right.

4. What can you say about the food colouring that was found in the filtrate along with the oil?

5. The procedure shown above attempted to isolate the oil from a given mass of muffin. Suggest two possible errors with the procedure given above and offer two ways to improve the procedure.
   

6. Consider the label on the right.

a. Identify 3 risks associated with the use of acetone.

b. For each safety risk, suggest one way to mitigate the risk.

 

Solutions
Individual student investigation - testing the oil content of two everyday food samples.