Determining Oil and Grease Concentration

The video tutorial demonstrates the determination of oil and grease in a water sample using gravimetric analysis. It outlines the materials and apparatus required, followed by a detailed step-by-step procedure. The process involves using petroleum ether to extract oil and grease, separating the layers, and calculating the concentration in parts per million. The tutorial concludes with a formula for computing the results.

What is the primary method used for determining oil and grease in this tutorial?

• Titration

• Spectrophotometry

• Gravimetric analysis

• Chromatography

Which of the following is NOT listed as a required material for the procedure?

• Analytical balance

• Water sample

• Petroleum ether

• Bunsen burner

How much petroleum ether is initially added to the separatory flask?

• 250 ml

• 150 ml

• 200 ml

• 100 ml

What is the purpose of shaking the separatory flask every 15 minutes?

• To sterilize the sample

• To cool the mixture

• To ensure proper mixing

• To evaporate the ether

What is done with the lower liquid after it is drained from the separatory flask?

• It is placed in another separatory flask

• It is combined with the upper layer

• It is discarded

• It is used for another test

What is the purpose of washing the top of the flask with water during the procedure?

• To ensure separation of layers

• To remove impurities

• To increase the volume

• To cool the mixture

Why is it important to let the contents settle after shaking the separatory flask?

• To ensure proper separation of layers

• To decrease the pressure

• To allow the ether to evaporate

• To increase the temperature

After combining the upper layers, what is the next step in the procedure?

• Adding more water

• Heating the mixture

• Evaporating the ether

• Filtering the solution

What is the final step in determining the concentration of oil and grease?

• Filtering the solution

• Adding more ether

• Calculating the parts per million

• Measuring the temperature

Which equation is used to compute the parts per million of oil and grease?

• Weight of beaker with oil minus weight of empty beaker divided by volume sample in liters times one thousand

• Volume of ether divided by weight of oil times one thousand

• Weight of oil divided by weight of beaker times one thousand

• Volume of water sample divided by weight of beaker times one thousand