It consists of sample injection port, carrier gas cylinder with pressure regulator, column oven, column (open tubular column and packed column), detector and data system. 1. Sample injection port A sample injection port is used to introduce the sample at the head of column. For optimum column efficiency, the sample should not be too large, and should be introduced into the column in vapour form. The slow injection of large samples may results in loss of resolution and band broadening.
The micropipettes were used for spotting the two silica TLC plates after each was dipped in a separate solution. Effort was made to avoid over spotting or cross contamination of the solutions. Both prepped silica TLC plates were placed in the Development Chamber (DC), that had 0.5% glacial acetic acid in ethyl acetate as solvent.
Zeinab Ossaili - 7654795 Synthesis Lab – Experiment 1: Separation By Distillation The objective of this experiment is: • To use simple distillation to purify liquids. • To experience the limits of simple distillation when it comes to separations. • To use fractional distillation to separate mixtures of liquids. Method used: Distillation 1 – Distillation of an organic liquid containing a non-volatile coloured impurity • The distillation apparatus was assembled in regards to the instructions given and this was done by setting up the heating mantle followed by the round bottom flask, the reduction adapter, still head, thermometer adapter and finally the thermometer. • After the above was assembled the still head was connected to the condenser which had the tubing connected to allow water in and out.
Abstract Gas chromatography (GC) and high performance liquid chromatography (HPLC) is an important technique which is used for the analysis of mixtures. In these instruments the mixture allows mixtures the instrument allows mixtures to separate in each components and determine the amounts of components present in sample. By using GC and HPLC we can analyzed a very small (microliters) sample. The sample which we want to analyze by GC must be volatile. The vaporized sample is allowed to flow in along tube having a porous material called column.
It is to prevent the cell from washing away during the staining and washing process. Then, it is air dried and followed by fixing it with flame from Bunsen burner. After fixing the smear, it must be stained using Gram staining solution, firstly crystal violet solution was flood onto it, and allowed for 1 minute, then wash off with tap water. Then, flood the slide with iodine solution for 1 minute and wash it off with tap water again. The formation of a dye-iodine complex will occur in the cytoplasm.
TLC was used to identify the actual unknown product as well as other products/reactants present in the filtered solution. The procedure was conducted by placing a TLC plate in a developing chamber that is filled with a small amount of solvent. The solvent cannot be too polar because it will cause spotted compounds on the TLC plate to rise up too fast, while a very non-polar solvent will not allow the spots to move. The polarity of the spots also determines how far it moves on the plate; non-polar spots are higher than polar ones. After spots on the TLC form, the Rf values are calculated and used to analyze the similarity of the compounds.
Aim The purpose of this experiment was to use fractional distillation technique to separate cyclohexane and toluene. Background Information Distillation is a technique which is used for separating two or more volatile products based on differences in their boiling points. Distillation can be used to separate a volatile solvent from a non-volatile product and separate a volatile product from non-volatile impurities. Simple distillation consists of a round-bottom flask, a distilling head, a condenser, an adapter and a receiver which are used to separate compounds where one is considerably more volatile than the other compound. This distillation is performed in one step.
Vitamin C titration is needed to perform this task in addition to standardizing of Iodine solution. This titration method is a redox reaction with potassium iodate in the presence of potassium iodide (Helmenstine, n.d.). The end point of the titration can be understood by the color change during titration. In this experiment, the addition of iodine to vitamin C in acidic solution with the presence of starch was stopped once color of solution started to change dark purple color from colorless
Answers 2 main hazards were acidified vanadate-molybdate reagent and sodium hydroxide. Especially for handling the acidified vanadate-molybdate reagent, the gloves and safety glasses must be worn and it has to be used in fume hood. For NaOH, must be careful when handling so that it does not spill. If there is a spillage, contaminated clothes should be removed, and rinse eyes, skin, clothes and equipment with lots of water and also must report supervisor. H₂PO₄⁻, HPO₄²⁻ present in pH of 7.25.
This causes the indicator to change colour due to the colour difference from the undissociate molecules. Strong acids and strong bases are strong electrolytes and are assumed to ionize completely in the presence of water. Weak acids however, only ionize to a limited extend in water. Any weak or strong acids when in contact with any weak or strong alkali will start to undergo neutralization regardless of their volume. When an indicator which is present in the acid-base mixture and have experienced colour change, it indicates that the mixture is in right proportions to neutralize each other and is also known as the equivalence point.