This experiment is predicated on the concept of utilizing liquid CO2 to extract D-Limonene from an orange’s rind and using optical rotation/refractive index to characterize the D-Limonene. Limonene is an essential oil which is found in orange peels. Limonene is classified as a monoterpene. This is because its structure consists of two isoprene units (C5H10). Limonene, like many essential oils, is categorized as a terpene/terpenoid. Terpenoids are oxygenated variations of terpenes. Terpenes are organic molecules that make up essential oils that can be found in many citrus fruits. Terpenes have structures made up of multiple isoprene units. These units are typically loosely assembled in a head-to-tail fashion (Weldegirma 2016). Terpenes are …show more content…
This light is referred to as plane polarized light (Weldegirma 2016). Polarimetry is also used to verify if a substance rotates the plane polarized light. The plane polarized light can rotate to the left, right, or not at all. A substance is considered optically active if it is able to rotate the plane polarized light to the either the left or right. A substance being optically active means that it has an enantiomer. To be optically active, the viewed substance must have a chiral center. A chiral center is defined as a carbon atom that has four different R groups linked to it. The positions of the 4 R groups determine which way the plane polarized light is rotated (Weldegrima 2016). Using a polarimeter to measure the substance’s optical rotation will help determine the optical purity of the substance. As polarized light passes through an optically active material, it rotates a certain amount. Measuring the degree of rotation of the polarized light will lead to the optical rotation being determined (Natt & Zhu, 2016). Polarimetric analysis of stereoisomers yields results that are represented in terms of Enantiomeric Excess (ee). Enantiomeric excess is also known as optical purity. To calculate the % ee the equation % ee = [α] Observed / [α] Pure * 100 is used. This equation allows
This is a contribution of the conjugated structure of the molecule that permits the absorption of the electromagnetic radiation in the visible spectrum of 400-700nm wavelength. In addition, the TPCP compound adopts a propeller shape in its three dimensional conformation. This can be described by the four phenyl rings are rotated out of the plane from the central ring due to the steric repulsion between the compounds. Lastly, after undergoing the synthesis process approximately 0.2 g of purified TPCP product was yielded. In other words, the theoretical yield was found to be 1.067 g, while the percent yield was determined to be 18.750%. (The calculations done to receive these digits could be found in the Calculations section of the article at the end of the article) The absorbance of the compound at 330 nm and 480 nm was predicted to be 1.1 and 0.2 respectively. Furthermore, the concentration of the TPCP using the equation displayed in the Calculations section at the end of the article was found to be 3.729*10-4 (330 nm) and 3.290*10-4 (480 nm).
Fluorescence measurement provides very important information about the photochemistry of a particular molecule. The first part of this experiment was dealing with the fluorescence behavior of a Leucophor PAF. Information from both spectrophotometry and fluorimetry was used to measure the quantum yield as well as to explain why Leucophor PAF was use as commercial optical brightener. The second part of this experiment dealing with fluorescence quenching of quinine bisulphate solution (QBS) is the presence of sodium chloride.
Introduction In this experiment, steam distillation was used to isolate eugenol oil from cloves. The goal of this experiment was to test and analyze the purity level of the eugenol oil that was isolated by applying a TLC test as well as H-NMR spectra. At the end of this experiment, eugenol oil was isolated, but some errors that occurred during the experiment resulted in impurities in the final isolated oil.
The IR spectrum that was obtained of the white crystals showed several functional groups present in the molecule. The spectrum shows weak sharp peak at 2865 to 2964 cm-1, which is often associated with C-H, sp3 hybridised, stretching in the molecule, peaks in this region often represent a methyl group or CH2 groups. There are also peaks at 1369 cm-1, which is associated with CH3 stretching. There is also C=O stretching at 1767 cm-1, which is a strong peak due to the large dipole created via the large difference in electronegativity of the carbon and the oxygen atom. An anhydride C-O resonates between 1000 and 1300 cm-1 it is a at least two bands. The peak is present in the 13C NMR at 1269 and 1299 cm-1 it is of medium intensity.
In order to separate the mixture of fluorene, o-toluic acid, and 1, 4-dibromobenzene, the previously learned techniques of extraction and crystallization are needed to perform the experiment. First, 10.0 mL of diethyl ether would be added to the mixture in a centrifuge tube (1) and shaken until the mixture completely dissolved (2). Diethyl ether is the best solvent for dissolving the mixture, because though it is a polar molecule, its ethyl groups make it a nonpolar solvent. The compounds, fluorene and 1, 4-dibromobenzene, are also nonpolar; therefore, it would be easier for it to be dissolved in this organic solvent.
Starting this experiment, we knew that the extraction was going to form varies layers due to the density differences. When placing three different substances, we saw that two layers formed because the Clove Oil is soluble in MTBE, but not in water. In order, to get the organic layer we used separatory funnel to take out the excess substances and leave the oil layer. Then we transferred to a beaker and dried with Magnesium Sulfate. Lastly, we filtered the liquid using funnel; we placed the liquid to boil, let it cool to room temperature. The purpose of drying and evaporation is to help us with the Gas Chromatography analysis of the product.
At a constant temperature, a pure liquid has a vapor pressure that describes the pressure of escaped gaseous molecules that exist in equilibrium at the liquid’s surface. Adding energy to a pure liquid gives more molecules the kinetic energy to break the intermolecular forces maintaining the liquid and raises the overall temperature of the liquid. Eventually, adding energy boosts the liquid’s vapor pressure until it equals the surrounding atmospheric pressure. When this occurs, the pure liquid boils at a temperature called the boiling point.
In this experiment, lipids from ground nutmeg are extracted using a combination of solvents and identify the lipids through chromatography. The purpose of using solvent combinations is to elute the lipids based on their polarity to binding of the silica gel. The chromatography is performed on a silica gel plate and the use of iodine to visualize the lipids. By calculating the Rf values for each compound and comparing them to the known lipids, we are able to distinguish the lipids within the grounded nutmeg.
Photosynthesis is, “the process by which plants convert light energy from the Sun into chemical energy in the form of carbohydrates” thus producing, “food for all living organisms, directly or indirectly” (Zheng). Photosynthesis has been examined in thousands of different ways. Many of these experiments include studying the rate of photosynthesis and pigment accumulation by obtaining plants and then stressing their light and nutrient intake (Okunlola and Adekunle). Photosynthetic pigments reflect and absorb different wavelengths of visible light based off their polarity. In this experiment, we studied photosynthetic pigments, first, by determining polarity and then, by measuring the amount of light of a given wavelength that a pigment absorbs. We used two methods in this experiment, chromatography and spectrophotometry. Chromatography “is a method used to separate mixtures of substances into their components” (lab book) and spectrophotometry is the use of a spectrophotometer to measure transmittance of light through a liquid. We used our knowledge of polarity to predict that since the least polar pigments move the most, pigment 1 is chlorophyll b, pigment 2 is chlorophyll a, pigment 3 is an anthocyanin, pigment 4 is a xanthophyll, and since most polar pigments move the least, pigment 5 is
The hypothesis stated that when the spinach extract was placed on the polar paper chromatography the pigment would separate into different pigments on the...
Chromatography is an extensive range of laboratory technique which aims to separate complex mixtures into their components which are distributed between a stationary phase bed and a mobile phase. There are various methods of chromatography. One method of mixture separation by chromatography is the column chromatography. Column chromatography gives a clear visual separation of components throughout the column. It is a cheap, simple method however it is time consuming. Another method of chromatography is thin layer chromatography which can be used to determine the number of components present within a mixture and to monitor column chromatography (Mohrig, et al., 2006). Thin Layer Chromatography is commonly used because it is a sensitive, speedy, easy and a rather inexpensive analytical technique of mixture separation. Examples of mixture that can be separated into their distinct components are chlorophylls from leaves of plants. Several different pigments are available from the leaves of the plant. Chlorophylls available in higher plants are chlorophylls a and chlorophylls b. Higher plant leaves also contain other pigments such as xanthophylls, carotenoids and phaeophytin. In some leaves, other pigments such as anthocyanins and antoxanthins may be found (Datta, 1994). All these pigments absorb light at certain wavelengths and appear as the color of reflected light. The aim of this practical is to understand the technique and principles of thin layer chromatography and column chromatography and identify the different pigments present within the leaves.
The fruits of citrus plants are known to grow on evergreen trees in subtropical areas worldwide that produce fruits with a variety of colors and shapes. Cross sections of the fruit show several identifiable layers. The outermost skin or rind, which normally exhibits a bright yellow or orange color, is the endocarp or flavedo. The endocarp protects the fruit from damage while secreting essential oils that give the fruit its characteristic odor (UNCTAD 2014). A white, spongy tissue known as the mesocarp (albedo) forms the second layer; it makes up the peel of the fruit and is typically removed before consumption (UNCTAD 2014)....
Generally, most of the properties of citrus plants are due to their essential oils and lime is one of the most important citrus fruits for the extraction of essential oil (Cruz-Valenzuela et al., 2017). Lime essential oils are defined as aromatic oily liquids that are obtained from the peel, leaves, twigs, and flowers of the lime or as a by-product obtained during the concentration of juice (Ruberto, 2002). They can be obtained by expression, fermentation, cold-pressing and extraction techniques but the method of steam distillation of fresh or dried lime is the most popular extraction method used for commercial production of essential oil (Ali et al., 2015).
Volatile oils are odorous constituents of the plants. They are liquid, lipophile, volatile with characteristic smell. Volatile oil will volatize or evaporate when exposed to atmosphere at ordinary temperature, so they are called ethereal oil. They also called as essential oil, as they essence or concentrated constituents of the plants. Volatile oils are insoluble in water, which is sufficient to impart taste and smell of the water and it is used for the preparation of aromatic waters in pharmacy. Volatile oils are soluble in alcohol, ether and other lipid solvents. Volatile oils are usually lighter than water. They have high refractive index and optical rotation. These oil present in entire part of the plant or other parts of plants like leaf, flower, bark, etc.... They are some important families that contains volatile oils are Labiatae, Rutaceae, Myrtaceae, Piperaceae and Zingiberaceae. Volatile oil present in structures as glandular trichomes,
Besides the use of essential oils in fragrances, there are approximately 3000 chemicals that are used in making of fragrance. It is used in many body care products and as well as perfumes, colons, and deodorants. As the studies have shown, such chemicals can trigger many different feelings hunger, nostalgia, happiness, or disgust. It is also used in many home products such as candles, cleaning products, laundry detergents, fabric care, and air fresheners. Fragrances are made with essential oils, which consists of extract of a plant. However, about 95 percent of the ing...