Results and Discussion Melting Point: Starting (°C) Final (°C) Rough Melting Point 139 159 Melting Point 131 133 Standard Melting Point 138 140 No correction had to be made to the melting points because the standard melted in the range labeled on the bottle. The melted point observed is the correct melting point.
For this lab, certain actions were performed to facilitate the optimal conditions for the Grignard reaction to proceed. As mentioned above, forming the Grignard reagent and the Grignard reaction must take place in dry, anhydrous conditions. This was why the glassware was initially placed in the oven to evaporate any moisture that was present on the glassware. Additionally, the magnesium used in the experiment needed to be dry too, so it was also placed in the oven to be heated. Creating a dry environment was also why the reaction vessel was covered in the septum because it helped prevent the moisture in the air from entering the reaction. Having water in the reaction vessel would destroy the Grignard reagent and hinder the Grignard reaction. Because the reaction needed to be done in dry and anhydrous conditions, diethyl ether was used as the solvent because it was aprotic meaning that the formation of phenylmagnesium bromide and the Grignard reaction would not be hindered by the protonation of water and alcohols3.
Abstract: The purpose of this lab was to synthesize triphenylmethanol from benzophenone and bromobenzene by the formation of a Grignard compound with the reagents bromobenzene and magnesium metal. The bromobenzene was first transformed into the Grignard compound and was then reacted with the benzophenone to make the final product. The mixture
Grignard reagents are reactive enough to also attach esters; however, two equivalents of the Grignard reagent are usually added because less then two equivalents leave a large quantity of unreactive ester. This reaction forms a tertiary alcohol.
re and reweigh to determine amount of solid solute (Neutral compound) • Obtain melting point Selecting Solvent for Crystallization • Perform the following with three 0.05g samples of unknown and the following solvents: methanol, water and toluene
Write the name of your element. Look the element up on your periodic table and record its symbol. Copy the following: Atomic Number is 92 The number of protons is 92 The number of electrons is 92 Atomic Mass Number is 238.0289 The number of neutrons is 146 What is its period? 7 group? 6 What is its melting point? 1,405 K: 1,132 C: 2,070 F. boiling point? 4,404 K: 4,131 C: 7,468 F
6. Data and Results The product of this experiment had a melting point of 58-60 °C and a weight of .014 g. Calculations showed that the limiting reagent was meso-stilbene dibromide. With that and the weight of the product, the percent
In determining the melting point range of the aspirin, a capillary tube (sealed at one end) was one-third-filled with the dried aspirin. The capillary tube and a thermometer were immersed in an oil bath. The temperature at which the solid started to melt and the temperature when the entire sample was completely liquefied were recorded as the melting point temperature range.
After each of the solids were completely dry, each was placed into a MelTemp device. The temperature at which each solid began to melt and completed melting was recorded.
Melting range would be closely related to a mixed sample whose constituents are most identical. In other words, melting point will have a wide range and would be below 200°C and above 95°C.
Discussion: As seen in the melting point determination, the average melting point range of the product was 172.2-185.3ºC. The melting points of the possible products are listed as 101ºC for o-methoxybenzoic acid, 110ºC for m- methoxybenzoic acid, and 185ºC for p- methoxybenzoic acid. As the melting point of the sample
A Grignard-Like Organic Reaction The Synthesis of 1-phenyl-3-buten-1-ol Introduction The Grignard reaction is an important synthetic process by which a new carbon to carbon bond is formed. Magnesium metal is first reacted with an organic halide forming the Grignard reagent. The Grignard reaction is the addition of an organomagnesium halide (Grignard reagent) to a ketone or aldehyde, to form a tertiary or secondary alcohol, respectively. For example, the reaction with formaldehyde leads to a primary alcohol. Grignard Reagents are also used in the following important reactions: The addition of an excess of a Grignard reagent to an ester or lactone gives a tertiary alcohol in which two alkyl groups are the same, and the addition of a
Physical properties* : Solubility – Very soluble (water), Freely soluble (methylene chloride, chloroform, alcohol), Slightly soluble (acetone) and Insoluble (ether).6 Melting point - 120°C or 248°F.5
The Grignard Reaction Abstract Through the use of the Grignard reaction, a carbon-carbon bond was formed, thereby resulting in the formation of triphenylmethanol from phenyl magnesium bromide and benzophenone. A recrystallization was performed to purify the Grignard product by dissolving the product in methanol. From here, a melting point range of 147.0 °C to 150.8 °C was obtained. The purified product yielded an IR spectrum with major peaks of 3471.82 cm-1, 3060.90 cm-1, 1597.38 cm-1, and 1489.64 cm-1, which helped to testify whether the identity of the product matched the expected triphenylmethanol. The identity of the product being correct was further confirmed by way of both proton and carbon-13 NMR spectra. This is due to the fact
References: Biology Online (2009). Osmoregulation. Retrieved from http://www.biology-online.org/dictionary/osmoregulation Biology Guide (2006). Principles of Homeostasis. Retrieved from http://www.biologyguide.net/bya7/bya7-16-11.htm Brittain, C. G. (2009). Using Melting Point to Determine Purity of Crystalline Solids. Retrieved from http://www.chm.uri.edu/mmcgregor/chm228/use_of_melting_point_apparatus.pdf