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Reading Assignment Goals and objectives of the experiment and the procedural sum

ID: 538594 • Letter: R

Question

Reading Assignment Goals and objectives of the experiment and the procedural summary laboratory notebook. should be written directly in your Pre-lab Questions I. Based on your knowledge of green chemistry, would you consider this procedure as “greener"? Explain your answer. 2· The liquid-liquid extraction process depends on two solvents be immiscible with each other and having different densities. a. What solvent will be used to extract caffeine from the aqueous tea layer? b. Record the density of this extraction solvent: c. Record the density of water: d. Which one will be the lower layer in the separatory funnel? e. What is the purpose of adding sodium chloride to the aqueous tea mixture? f. What is the purpose of adding sodium carbonate to the aqueous tea mixture?

Explanation / Answer

Answer:

2)

a) Chloro form is used for the extraction of Caffeine.

b) Chloro form density = 1.49 g / cm3

c) water density = 1 g / cm3

d) Chloroform is lower layer in separating funnel

Explanation: More density one become as a lower layer.

e) Addition of Sodium chloride the Caffein come out from the aqueous layer during the extraction process.

Note: NaCl is the Inorganic salt so it is sparingly soluble in the water as a result of this the coffein come out during the extraction.

f) Sodium carbonate acts as base during the Isolation of the caffein.

When we are boiling the Tea leaves with the water, The coffein and the Tannins dissolve in the water. During the extraction process coffein and the Tannins can be extracted. To avoid the Tannins the Sodium carbonate is used as a base.

3)

a) Ethyl acetate - Top

   Water - Bottom

water density is more. Hence it become as a bottom layer.

Both are Immiscible.

b) Ethanol and Water both are miscible.

c) Water - Top

   Chloroform - Bottom

Chloro form density is more than water

Both are Immiscible.

4) Drying of an Organic layer:

Drying of the Organic layer means to remove the water or moisture from the Organic layer.

The drying agent are like Na2SO4 and MgSO4

5) Answer:

Solid to gaseous phase convertion is called Sublimation.