The objectives of this experiment are to synthesis 1-bromobutane from n-butanol under reflux setup via SN2 mechanism
Singapore Polytechnic School of Chemical and Life Sciences Diploma in Applied Chemistry with Pharmaceutical Science Experiment 4 Preparation of 1-bromobutane Desmond Seah 006812 DACP/FT/2A/21 Date of Experiment: 28 January 2012 Date of Submission: January 2012 ________________ Introduction ________________ Aims The objectives of this experiment are to synthesis 1-bromobutane from n-butanol under reflux setup via SN2 mechanism, and crude purification is carried out using distillation followed by series of solvent extraction. The yield and density of 1-bromobutane will then be determined. 2 Introduction The mechanism of this reaction belongs to SN2 – Bimolecular nucleophilic substitution. Figure 1: Reaction Scheme (ChemDraw) The starting material is a primary monohydric alcohol (n-butanol) and can be prepared be the reactions below: Figure 2: Preparation of Alcohol (Mehta, 2006) Based on the figure 2, the addition of water-hydrolysis of but-1-ene will not be able to give us a primary butanol instead it will give us a secondary butanol. It is because reaction is an electrophilic addition reaction and follows Markovnikov’s rule. Therefore, we have to use oxymercuration-demecuration process in alkene or hydroboration oxidation in but-1ene to prepare the primary alcohol. In a bimolecular mechanism, the attack of nucleophile (Br-) on sp3
Forensic Chemistry - Ion Selective Electrode. The objective of experiment is to determine the chloride and nitrate (toxic anions) in samples from the calibration curve
SINGAPORE POLYTECHNIC SCHOOL OF CHEMICAL LIFE SCIENCES Diploma of Applied Chemistry with Pharmaceutical Science Experiment No. 3 Metal Toxicity Module Code (CP 4098) Desmond Seah (P1006812) Year of Study: Year 2 DACP/FT Lecturer Jeffrey Whey AY 11/12 ________________ Content Page Synopsis Page . Introduction 1-2 2. Theory 2-12 3. Procedure 12-13 4. Results and calculation 13-14 5. Discussion 14-24 6. Conclusion 24 References List of Illustration S/N Figures and Tables Page Number Types of electrode with diagram 7 2 Internal structure of Ion selective electrode 8 3 Possible interferences with reference solutions stated 9 4 Calibration curve of Ion
Copper Penny Lab Report - measuring density.
Is it a Copper Penny? Measuring Density Experiment Date: 30 September 2010 Due Date: 8 October 2010 Is it a Copper Penny? Measuring Density Objective The objective of the experiment is to calculate the densities of pennies and determine the unknown compositions of pennies minted in 1943, and compare the accuracy and precision of the results to the known densities of pennies minted between 1962 and 1982 and those minted after 1982. Materials . Balance 2. 100 mL graduated cylinder 3. 35 pennies minted between 1962 and 1982 4. 35 pennies minted after 1982 5. 35 pennies minted during 1943 6. Paper towels Procedure . 2 pennies minted between 1962 and 1982 were placed and weighed for mass on a balance and the respective mass was recorded. 2. The 2 pennies were then placed in a graduated cylinder containing 20 mL of distilled water in order to find the volume of the pennies inside the water. 3. The displacement of the water, after the 2 pennies were added, was recorded as the volume. 4. Step 1 was repeated using a new set of 13 pennies minted between 1962 and 1982. 5. These 13 pennies were then added to the graduated cylinder containing 20 mL of distilled water and the set of 2 pennies. The new displacement of water was recorded to tenths of a milliliter. 6. Again step 1 was repeated using a new set of 20 pennies minted between 1962 and 1982. 7. The set of 20
SN1 Reaction: Preparation of Cyclohexyl Chloride
Experiment 8: SN1 Reaction: Preparation of Cyclohexyl Chloride RESULTS Substance Volume Observations Cyclohexanol 5mL Thick, clear liquid Volume after reflux 4.5 mL After 10 minutes of heating liquid in r.b flask was cloudy After 30 minutes two separate layers were visible, the upper layer being a clear yellow, the lower layer being white and translucent Volume after 1st drying w/.45g drying agent 3.6 mL After separation the organic layer became whitish in color but not opaque Volume after 2nd drying w/ .35g drying agent 2.2 mL A second drying was used to obtain a purer product but no change was observed in its appearance Theoretical Yield 5.0 mL Actual Yield 2.2 mL Percent Yield. 44 % Qualitative Test Results Observation Chromic Acid + Yellow color was still observed but after some time dark greenish precipitate began to form in the bottom of the test tube, although the yellow color was still present, possibly due to low amounts of alcohol in the mixture Silver Nitrate + Formation of tiny white solids when silver nitrate was added DISCUSSION Experiment 8 examined SN1 reactions which are reactions that synthesize alcohols where the rate-determining step in uni-molecular. This reaction contains a leaving group which leaves resulting in a carbocation that is immediately attached by a nucleophile that is commonly a weak base. 3 The rate of
Determination of the density of an unknown liquid
EXPERIMENT 1 Title: Determination of the density of an unknown liquid Objective: To determine the density of a liquid using pycnometer method. Introduction: In order to classify and identify materials of a wide variety, scientists use numbers called physical constants (e.g. density, melting point, boiling point, index of refraction) which are characteristic of the material in question. These constants do not vary with the amount or shape of the material, and are therefore useful in positively identifying unknown materials. Standard reference works have been complied containing lists of data for a wide variety of substances. The chemist makes use of this in determining the identity of an unknown substance, by measuring the appropriate physical constants in the laboratory, consulting the scientific literature, and then comparing the measured physical constants with the values for known materials. This experiment illustrates several approaches to the measurement of the density of liquids and solids. Density is a measure of the “compactness” of matter within a substance and is defined by the equation: Density = mass /volume The standard metric units in use for mass and volume respectively are grams and milliters or cubic centimeters. Thus, density has the unit grams/milliter (g/ml) or grams/cubic centimenters (g/cc). Density determination by pycnometer is a very
