Determine the amount of compound remaining in the aqueous phase and organic phase and organic phase if a 5.0g organic compound is dissolved in 100 mL of water and is extracted with three 50-mL portion of ether (kb= 10). Compare this with one 150 ml portion with ether. Which is more efficient?
To determine the amount of compound remaining in the aqueous phase and the organic phase after extraction, we need to understand the principles of solvent extraction and use the distribution coefficient (Kd).
The distribution coefficient (Kd) is a measure of how much compound will partition into each phase. It is calculated as the ratio of concentrations of the compound in the organic phase to the concentration in the aqueous phase. It can be expressed as:
Kd = [organic phase]/[aqueous phase]
In this case, we are using ether as the extracting solvent, and its distribution coefficient (Kd) is given as 10. It means that the compound is ten times more likely to partition into the organic phase compared to the aqueous phase.
Now, let's calculate the amount of compound remaining in each phase for both scenarios:
1. Extraction with three 50 mL portions of ether:
- Initially, the compound is dissolved in 100 mL of water.
- Since there are three 50 mL portions of ether, we can assume that each portion has an equal volume as the amount of water.
- After the first extraction with ether, 100 mL of water will contain a smaller amount of the compound, while the ether will contain a larger amount.
- Repeat the above step two more times for the remaining two portions of ether.
- Finally, we calculate the remaining amounts of the compound in each phase by applying the distribution coefficient (Kd = 10) to the initial amounts.
2. Extraction with one 150 mL portion of ether:
- Here, we perform a single extraction with the entire 150 mL portion of ether.
- Again, we calculate the remaining amounts of the compound in each phase using the distribution coefficient (Kd = 10).
Now, let's compare the efficiency of the two methods:
To determine which method is more efficient, we compare the total amount of compound recovered in the organic phase between the two extraction methods.
You can calculate the amount of compound recovered in the organic phase for both scenarios and compare the values. The method that yields a higher amount of compound extracted into the organic phase is more efficient.
Note: It's important to remember that efficiency is not solely dependent on the amount of compound recovered but also the solubility of the compound in the organic and aqueous phases, as well as the distribution coefficient.