Chromatography

Student name: Amal Al-Hamdani Teacher name :Alia Alfi Group name: 2 Year: 2018 Chromatography  is  a physical method  used in lab  for  separation of  a mixture of chemical substances into its individual components, so that the individual components can be thoroughly analyzed.  it has numerous applications in  biological  and  chemical  fields.  it  is widely used in  biochemical  research for the separation and identification of  chemical compounds  of biological origin. Chromatography  consists of two  phase;  a  mobile phase  (a liquid or a gas)  , which  Ã‚  flows through  the  stationary  Ã‚  phase  , and a  stationary  Ã‚  phase  (a solid) .the stationary phase has certain physical and chemical characteristic that allow it to interact in various ways with different compound . A common types of  Ã‚  stationary  Ã‚  phase  Ã‚  are ;ion exchange chromatography, Affinity Chromatography, Gas Chromatography, liquid Chromatography†¦etc.Gas ChromatographyGas Chromatography  (GC)  or,  gas-liquid chromatography (GLC)  is a useful  tool  technique  that, allows us to separate and identify individual components in the mixture.  also, Gas Chromatography  can measure the concentration  of various components in the mixture for samples that have volatile  components  and,  separate mixture  by adherence to a surface. Method: 3590925369570000 A gas chromatograph uses a flow-through narrow tube known as the column, through which different chemical constituents of a sample pass in a gas stream (carrier gas, mobile phase) at different rates depending on their various chemical and physical properties and their interaction with a specific column filling, called the stationary phase. As the chemicals exit the end of the column, they are detected and identified electronically. The function of the stationary phase in the column is to separate different components, causing each one to exit the column at a different time (retention time). Other parameters that can be used to alter the order or time of retention are the carrier gas flow rate, For example, internal standards it is commonly used way in  Gas Chromatography to calculate  the  concentration of an analyte. for any particular detector, the relative response factor for the  analyte compared  to the  internal standards must be determined first. calibrating the linearity of the response factor for the  analyte compared  to the  internal standards requires making a series of the solutions with the same concentration of the standards, and a varying concentration of analyte. Plotting the response of the analyze relative to the standard (peak area of analyte/peak area of standards) versus the concentration of the analyte relative to the standard ([analyte]/ [ standard]) should produce a straight -line graph whose slope in the response factor.C+O2? CO2 +heatThis is a fast reaction and there a lot of physical method to slow down and stop fast reactions for example:Reducing the temperature at which a reaction occurs i.e. cool things down.adding a reagent which will react with the remaining reactantUsing reagents that have a small surface area i.e. the substance is in large lumps.Using a catalyst – the right catalyst can slow down the rate at which a chemical reaction occurs.The rate of reaction for a concentrated strong acid with a concentrated strong base is most affected by what three things the use of a catalyst, a change in temperature, a change in reactant concentration.We are going to use temperature temperature normally speed the reaction and i t also slow it down by lowering the it because the rate and the temperature has a Positive relationship so if temperature is high the reaction speed increase and if the temperature is low the reaction speed decrease and that is according to  van't Hoff's law,  an increase in temperature will cause an increase in the rate of an endothermic reaction. The effect of the temperature can be explained by the fact that increasing temperature will move the particles at higher speeds and the impact of the collisions leading to the interaction is large, which increases the speed of the reactionand also, at higher temperatures, higher percentages of collisions produce a chemical reaction because higher percentages of molecules have greater velocity, and enough energy is available to react. Explanatory examples tell the effect of temperature on the rate of chemical reaction rateIncreased temperature helps to speed the maturity of food.Increasing the pressure in the pressure vessels leads to an increase in temperature inside the so the food is cooked very quickly.Keeping food in the refrigerator help not to spoil it because the temperature of the refrigerator is low, and this leads to a decrease in the speed of geochemical reactions that cause food corruption.The temperature change in the chemical balanced reaction, leading to the interaction in the opposite direction, which cancels the effect of this change Interpretation In the case of heat-reactive reactionsI-Reduce the temperature The interaction is facilitated in the direction that reduces the effect of lowering the temperature (which reduces the effect of this effect), ie, the reaction in the direction that causes the increase in temperature is the random directionII-when raising the temperature. The interaction in the direction that reduces the effect of raising the temperature (which reduces the effect of this effect) is facilitated by the interaction in the direction that causes the temperature reduction and is the reverse direction So, in the reaction I did chose it is a exothermic so when we raising the temperature it will slow down the reaction because it is exothermic and when it dose slow down the molecules in the reaction will be slower in moving and the collisions and if it was endo thermic the opposite will happen. And we cannot calculate the rate law because it is experimentally calculated so we can only write the rate low for the reaction C+O2? CO2 +heat Rate low ReferencesPage 1^ â€Å"Gas Chromatography†. Linde AG. Archived from the original on 3 March 2012. Retrieved 11 March 2012.^ Jump up to: a b c d e f g h i j k l m n o p Harris, Daniel C. (1999).â€Å"24. Gas Chromatography†. Quantitative chemical analysis (Chapter) (Fifth ed.). W. H. Freeman and Company. pp.  675–712. ISBN  0-7167-2881-8.Page 2 Chromatography Search the web. Some interesting sites are listed below. Note that some of these sites go into much more depth than is reasonable for this course. http://en. wikipedia. org/wiki/Chromatography http://ull. chemistry. uakron. edu/analytical/Chromatography/ http://orgchem. colorado. edu/hndbksupport/TLC/TLC. html this is for TLC – similar to paper http://users. rcn. com/jkimball. ma. ultranet/BiologyPages/C/Chromatography_paper. html http://jchemed. chem. wisc. edu/JCESoft/Programs/CPL/Sample/modules/paprchrom/paprchromdesc. htm http://jchemed. chem. wisc. edu/JCESoft/Programs/CPL/Sample/modules/paprchrom/paprchromdesc. tm This site shows the colors of many of the food colorings and lakes http://www. dynemic. com/food%20colour. htm This site has colors and correct names for many of the colors. You can get the structures from the names with CRC or a good organic chemist. http://vm. cfsan. fda. gov/~lrd/colorfac. html this is a general site with information on food colorings â€⠀œ discusses difference between dyes and lakes Procedure – Extract the color from the candies 1. Label each of the beakers with one color of the candy. 2. Place one sample in each cup. 3. Put as few drops of water as possible (around 5) in each cup. 4. Stir carefully to extract as much color as possible without disturbing the white coating or the centre of the candy. 5. Remove the sample as soon as the white coating appears. 6. Add each sample in turn to its appropriate cup until as much color has been extracted as possible. Note: Repeat the steps for each kind of candy. Be sure to include the color and kind of candy on your label. Prepare chromatogram 1. Cut a piece of chromatography paper in half to form a rectangle with dimensions 10 cm x 20 cm. 2. Draw a line approximately 1 cm from the long edge of the paper with a pencil. 3. Mark dots along the pencil line approximately 1-1. cm apart and label as food dye colors yellow, green, blue, and red. Mark two additional dots for your choice of two different colored candies. 4. Using a toothpick, carefully wet the spots you have marked with the appropriate food color or the color extracted from your candy. As the spots dry, rewet them with more sample until you have a dark spot. (If yo u do not load enough sample onto the chromatographic paper it will be difficult to detect the spots. ) 5. Curl the paper into a cylinder with the short edges just touching and staple together. 6. Place the chromatogram into a beaker with approximately ? m of solvent on the bottom. Be sure that the entire lower edge of the chromatogram is touching the solvent, but the solvent does not reach above the pencil line. Allow the chromatogram to sit in the beaker until the solvent front is 1 cm from the top of the paper and remove. Draw a line at the solvent front with your pencil. 7. Repeat this process for any additional solvents you wish to use. Analysis of chromatogram. 1. Circle each spot that you see on the chromatogram. 2. measure the distance between the starting point and the center of the spot for each component on your chromatogram 3. easure the distance between the starting point and the solvent front on your chromatogram 4. Calculate the Rf value for each component. 5. Draw con clusions regarding the identity of each component in the chromatogram. 6. Propose reasons why different components had higher or lower Rf values based on the structures below and your knowledge of intermolecular forces. Colors ProductRedYellowGreenBlue Crown Colony KitBlue #1 Red #3 Red #40Yellow #5 Yellow #6Blue #1 Yellow #5Blue #1 Crown Colony SinglesRed #40Yellow #5 Red #40Blue #1— DurkeeBlue #1 Red #3 Red #40Yellow #5Blue #1 Yellow #5Blue #1 McCormickRed #3 Red #40Yellow #5 Yellow #40Blue#1 Yellow #5Blue #1 Red #40 FDA Certifiable colors: (name/common name) NameCommon nameComment FD&C Blue No. 1Brilliant Blue FCF FD&C Green No. 3Fast Green FCF FD&C Red No. 3Erythrosine FD&C Red No. 40Allura Red AC . It usually comes as a sodium salt, but can be also in the form of calcium and potassium salt. It is soluble in water. FD&C Yellow No. 5Tartrazine FD&C Yellow No. 6Sunset Yellow FCF Questions 1. Does the type of solvent used for paper chromatography affect the Rf values of the food dyes? 2. Which dye molecules were in your candy coating? 3. If the solvent front moved 112 mm and a component of a mixture moved 48 mm