Pre- lab preparation To perform this investigation, a number of the solutions were needed to be prepared in advance. The following is the preparation process - Preparing the stock solution-The stock solution of Salicylic acid needed to be prepared well in advance before the experiment began. To do so, 1.73g of Salicylic Acid was weighed using the weighing balance. After Salicylic acid was weighed, it was transferred to a standard flask of 100cm3 and, 100cm3 of pure Ethanol (C2H5OH), was poured into the standard flask that contained the Salicylic acid. Shaking the flask gently for C2H5OH and Salicylic acid to dissolve and then keeping it covered so that C2H5OH did not evaporate. Label the solution as SS (stock solution), 0.0125 mol dm-3. Concentration of Salicylic Acid Mass/(Molar Mass)=Concentration ×Volume ⇒1.732/138.121= Concentration ×100cm3 Therefore, Concentration=0.121 mol dm-3 Preparing the HCl of varying concentrations- Volume of water required to dilute- Cinitial× Vinitial= Cfinal× Vfinal 0.1×V =0.01 × 100 V = (0.01×100)/0.1=10 cm3 ⇒Vwater=100-10=90cm3 Preparing pH of 1-To do so, a volume of 1cm3 solution with a molarity of 0.1M was used. In the process of creating a pH solution of 1, the original concentration of HCl, which was 1cm3 and 0.1M was used for pH 1, and three samples of this concentrations were made. To make sure that the pH for each trial was the right pH, a pH probe was used. Hence, the original pH of HCl was 1.13. Preparation of increasing
The contents of the reaction flask were slowly poured into the 250 ml Erlenmeyer flask which already contained 13.75 g ice and 25 ml of 10% H2SO2. The round bottom-flask was rinsed with 2.0 mL of 10% H2SO4 and 2.0 mL of diethyl ether, and the rinses were added to the mixture in an Erlenmeyer flask. Then, the mixture was swirled until all the salt was hydrolyzed, and the product distributed well into the ether layer. A
Prelab week 1 Calculations Preparation of 1.5μmol/L mixed low-level standard dilution 150μmol/L × V1=1.5μmol/L × 10ml V1=(1.5μmol/L×10ml)/(150μmol/L)=0.1ml Conversion of milliliters to microliters (0.1ml×1000)μL= 100μL Preparation of 3μmol/L mixed low-level standard dilution 150μmol/L × V1=3μmol/L × 10ml V1=(3μmol/L×10ml)/(150μmol/L)=0.2ml Conversion of milliliters to microliters (0.2ml×1000)μL= 200μL Preparation of 3μmol/L mixed low-level standard dilution 150μmol/L × V1=7.5μmol/L × 10ml V1=(7.5μmol/L×10ml)/(150μmol/L)=0.5ml Conversion of milliliters to microliters (0.5ml×1000)μL= 500μL Preparation of the blank samples The volumetric flask will be filled to the mark with 150μmole/L of stock solution to act as blank (reference). Additional two blanks will
The average HCl concentration of the three trails is = 0.098 M 2. Question 2: Experiment 2: The acidity and vinegar, the type of vinegar we used was Kroger distilled white vinegar, and the acidity of the vinegar was 5% Trails Dilution of original vinegar solution. Volume of
Next, about 10 mL of both solutions, Red 40 and Blue 1, were added to a small beaker. The concentration of the stock solution were recorded, 52.1 ppm for Red 40 and 16.6 ppm for Blue 1. Then, using the volumetric pipette, 5 mL of each solution was transferred into a 10 mL volumetric flask, labelled either R1 or B1. Deionized water was added into the flask using a pipette until the solution level reached a line which indicated 10 mL. A cap for the flask was inserted and the flask was invented a few times to completely mix the solution. Then, the volumetric pipette was rinsed with fresh deionized water and
After obtaining an homogeneous mixture, the flask was placed in an ice bath during five minutes next to a graduated cylinder containing 5.0 mL of concentrated sulfuric acid. The temperature of the ice bath was recorded to be 1.1 °C. Likewise, a second graduated cylinder containing 1.8 mL of nitric acid and 2.5 mL of sulfuric acid was immersed in the cold ice bath to keep the three different solutions at the same temperature. Thereafter, the cold 5.0 mL of H2SO4 were added to the erlenmeyer flask containing the acetanilide solution, which remained in the cold water for approximately another 4 minutes.
In the round-bottom flask (100 mL), we placed p-aminobenzoic acid (1.2 g) and ethanol (12 mL). We swirled the mixture until the solid dissolved completely. We used Pasteur pipet to add concentrated sulfuric acid (1.0 mL) to the flask. We added boiling stone and assembled the reflux. Then, we did reflux for 75 minutes.
Results: Table 1: Results from the Salicylic acid (g) and the Purity of ASA (g) Experiment Mass of salicylic acid (g) 0.14 g Mass of filter paper (g) 0.47 g Mass of “impure” ASA + filter paper (g) 0.56 g Mass of prepared “impure” ASA (g)
= 10^-3 M = 1,000 mL Here C1,C2; are the first and second concentrations of solution V1 and V2 ; are the required and current volumes. The impeller turned on and DDA, and tap water left to be mixed properly with water for 2 minutes. Approximately 150 grams of quartz added into the solution.
Pat McGurrin October 24, 2015 Period #1 Honors Biology Mr. Dinunzio Murder and Meal Lab Analysis Procedure: 1.) Gather all materials: Safety goggles, 250ml beaker, water, hot-plate, test-tubes, paper bag tear, stomach contents, pipette, Biruet solution, Benedict’s solution, and Iodine solution. 2.) Put on safety glasses.
Rediet Legese iLab Week # 6 CRUDE OIL DISTILLATION Introduction: The aim of this week lab experiment is to experiment distill crude oil and to check how temperature determine the chemical properties of crude oil plus how the boiling point can also show physical properties. They are two major finding in this experiment. he first finding was the point at which the raw petroleum is heated to the point of boiling, at 275 0C, the gas and kerosene oil are refined, however the oil (lubricant ) stays as an unrefined feature oil.
A 50 mL buret was obtained and was washed with NaOH solution. After filling the buret with NaOH (titrant) and preparing the KHP (analyte) in the Erlenmeyer flask, the solutions were titrated. The volume used from the NaOH solution was recorded. C. Determination of the Acidity of Soft Drinks First, the soft drinks were heated.
The developing solution was poured into a tank and was tightly covered with a glass lid, and the tank was allowed to be saturated to ensure that the solution was equilibrated in the gas phase. Silica plate for TLC analysis: A horizontal line was drawn with a pencil on the plate and it was about 1 cm above the bottom of the plate. The horizontal line was drawn faintly so as to avoid damaging the silica gel on the plate. On the horizontal line, two marks were made and one was named A and the other B. These marks were made towards the centre of the plate at a distance apart because when spots are made at the edge of a plate, the result would be an improper travel of the samples as the solvent advances on the plate.
Once dissolved, fill the rest of the volumetric flask up to the line on the neck of the flask. Again mix the solution. Use four, 10mL volumetric flask, and label them from 1-4. Add approximately 2mL of copper sulfate pentahydrate into flask 1, 4mL to flask 2,
Introduction Buffer is a solution that resists a change in pH when bases or acid are added. Solutions that are acidic contain high concentrations of hydrogen ions (H+) and have pH values less than seven. Buffer usually consist of a weak acid, and its conjugate base or a weak base and its conjugate acid. The function of buffer is to resist the changes in hydrogen ion concentration as a result of internal and environmental factor. This buffer experiment is important so that we relies the important of buffer in our life.
The chemical equation for this experiment is hydrochloric acid + sodium thiosulphate + deionised water (ranging from 25ml to 0ml in 5ml intervals) sodium chloride + deionised water (ranging from 25ml to 0ml in 5ml intervals) + sulphur dioxide + sulphur. As a scientific equation, this would be written out as, NA2S2O3 + 2HCL + H2O (ranging from 25ml to 0ml in