What was green about this experiment? Minimum one suggestion with reference to a

Question

What was green about this experiment? Minimum one suggestion with reference to a specific GCP number. THEORY Recrystallization is a common laboratory practice used to purify a compound. The first st is to decide on an appropriate solvent. An ideal solvent is one in which the solid to be purified is insoluble at room temperature, but much more soluble at a higher temperature. The cold relativel solvent must also be able to dissolve impurities that are to be removed. Finding the correct solvent requires some that are more soluble then the compound be are easily removed by crystallization, since they will be retained by the mother liquor (the liquid remaining after crystallization has taken place). Impurities with solubility similar to the substance being purified that are present in low concentrations will also remain in the solution, and can be easily removed. If there are mechanical impurities such as sand, dust or cork that do not dissolve even upon heating, the hot solution can be gravity filtered to remove these. In the case of coloured impurities, a small amount of decolourising carbon (charcoal) can be added to the hot solution. The carbon is then removed as a mechanical impurity. Excessive amounts of d carbon should be avoided, since it may adsorb the compound that is being purified. To ensure that most of the substance being purified can be recovered, it is essential that the least amount of hot solvent needed to dissolve the sample is used. It is good practice to err on the side of insufficient solvent, since more can be easily added in small increments until enough is present. Sometimes, an ideal solvent cannot be found. In such a case, a mixture of two solvents, a solvent-pa A t-pair is required. solvent made up of two mutually soluble liquids, one that dissolves the substance easily and that dissolves it sparingly. The solid to be dissolved in a minimal volume of th first solvent at room temperature. The second solvent is then added gradually until the solution becomes Heating followed by cooling typically leads to a suc recrystallization. Some examples of common solvent-pairs include water and ethanol, cyclohexane and ethyl acetate, and glacial water. The melting point will be determined using a Mel-Temp apparatus i the lab. A "pu sample of acetanilide is generally one in which the melting point is within egress Celsius of expected. UNDERSTANDING THE EXPERIMENT You begin the experiment with acetanilide, which is contaminated with traces of water luble Methyl Red, 5% by weight sand and 5% by weight benzoic acid. The goal of this experiment is to remove these impurities To tart off, the sample needs to be dissolved. This will get the soluble impurities, benzoic acid and Methyl Red as well the acetanilide into solution. Next, the sample is treated with which dsorbs the coloured impurity (Methyl Red. Gravity filtration of the hot solution uble impurities, namely sand and charcoal (as well as the Methyl Red adsorbed by the charcoa). The solution now containing just acetanilide and benzoic acid is allowed to cool slowly, and acetanilide crystallizes. B ble in water then acetanilide and found in enzoic acid is more solu lower concentration, so it will Vacuum filtration is used to collect the remain in the mother liquor.

Explanation / Answer

The process is considered green Ifminimal amount of solvent is used in. Here we are using minimal amount of organic solvent.

Also water is a green solvent with no side effect, which makes the process green.

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