Comparative Hl Titration Of Hcl

“Comparative pH titrations of strong and weak acids” Experiment #6 – The aim of the experiment is to titrate a strong acid and a weak acid with a primary standard solution NaOH and finding its pH. The titrant NaOH which is 1M is filled in the burette. Below the titrant, a 250-ml beaker is positioned is such a way that while titrating the NaOH is poured down the beaker which is filled with a solution of 75-ml of DI water and 25-ml of HCL. In order to begin titration, the electrode is put into the beaker such that it doesn’t hit the spinning stir bar. A magnetic stir bar is kept underneath the 250-ml beaker so that the mixture gets dissolved faster.

The pH meter needed to be calibrated before the titration, and this was done by using coloured standards of pH 4.0, 7.0 and 10.0. The NaOH used within this practical was measured out in pellet form, and the amount needed was 0.4g of 0.1M NaOH. The NaOH was then dissolved into 100ml of distilled water by using a magnetic stir bar and a magnetic stirrer, which mixed the solution for around 120 seconds. After the NaOH had been dissolved, 25ml of 0.1M CH3COOH was measured into a measuring cylinder and was then transferred into a 100ml beaker. This was also placed onto the magnetic stirrer and a clean magnetic stirrer bar was then added to avoid any contamination before the NaOH had been added.

0.5ml of extract along with 0.1 ml of (0.5N) Folin-Ciocalteu’s reagent was incubated at room temperature for 15 min. After incubation, 2.5 ml of saturated sodium carbonate solution was added and further incubated for 30 min at room temperature. The absorbance was measured at 760 nm. Gallic acid was used as a positive control. Total phenol content was expressed in terms of gallic acid equivalent (mg/g of extracted compounds).The assay was carried out in triplicates and expressed as mean±SD.

Title: Potentiometric Titration Purpose: The purpose of this lab was to construct a titration curve by titrating Formic acid using a standardized sodium hydroxide (NaOH) and a pH meter through potentiometric titration. After the data for the rest of the class is collected, compare and contrast the equivalence points to see how the concentrations of the various acids affected the acids weakness and strength. Methods: Obtain 0.020 M of Formic Acid (HCCOOH). Calibrate the pH meter using the instructions for calibrating the pH meter in the appendix. After the calibration of the pH meter, 150 mL of Formic acid solution was dispensed into a clean dry beaker, and then 50 mL of the formic acid was transferred into a 250mL beaker.

Apparatus: 2g potassium chlorates, some distilled water, a stand, a clamp, two beakers, a thermometer, a test tube, and a measuring cylinder. Method: 1. Put the potassium chlorate into the test tube, and then put 4g distilled water. 2. Then the solute (which is the salt) dissolves in water (the solvent) by heating.

1. Estimation of Aceclofenac and re-leated substances. (IP 2010) • Liquid chromatographic sys-tem: • Column: a stainless steel col-umn 25 cm x 4.6 mm packed with spherical end-capped octadecylsilane bonded to porous silica (5µm), with a pore size of 10 µm and carbon loading of 19 per cent • Mobile phase: A. a 0.112 per cent w/v solu-tion of orthophosphoric acid adjusted to pH 7.0 using a 4.2 per cent solution of sodium hydroxide, B. 1 volume of water and 9 volumes of acetonitrile • Flow rate: 1 ml per minute • UV detection: 275 nm • Injection volume:10 µL 23 2. Assay of aceclofenac (IP 2010) • Weigh accurately about 0.3 g and dissolve in 40 ml of me-thanol.

Using acid that is twice the molar of the alkali should result in equal volumes of each being used. So * 0.013 * 2 = 0.026 M *and taking the molar of the acid down by a factor of one hundred would work well. Calcium hydroxide and hydrochloric acid are in the ratio 1:2. For this, I will need the pipette and the pump to collect exactly 25cm3 taking into account parallax errors where the level of the 25cm3 line is at the bottom of the meniscus. By placing this in a volumetric flask and topping it up to 500cm3 with distilled water taking into account the parallax error again.

A substitute we used the thermometer. Methods Trial Test In a 100ml beaker 30mls of water was placed the temperature of the water was recorded. 1 teaspoon of Ammonium Nitrate was added to the water and stirred until dissolved. The temperature was then recorded again. This was to see the difference between the initial temperature and the final temperature.

2.5.2 Kinetic investigation of FVS in oxidative degradation The kinetics of the acid degradation of FVS were evaluated in 3 % H2O2 at 70°C for different time periods. Solutions containing 1 mg/mL of the FVS were prepared in water. An appropriate aliquot was transferred into a volumetric flask, and diluted with 3 % H2O2 to give final concentration of 100µg/ml FVS. This solution was heated to 70°C, evaluated for time intervals of 30 min, 60 min and120 min. Three samples were analyzed for each time interval.

In the early stages of the reaction, the first 60 min, phenol conversion was 30% and increased slightly up to 47% after 120 min. We assume this may be due to the fact that as tert-butanol was consumed in the reaction, fewer molecules were left in the reaction mixture and more time was required to generate the carbocation from the tert-butanol. Further, initial rate of desorption of the product from the catalyst surface is high and as the concentration of the product increases in the reaction mixture the rate become slowly. During the first 2 hours, only the formation of 2-TBP and 4-TBP was observed which may be because of more available phenol around Brønsted acid sites to react with tertiary carbocation. After that, there is a decrease in the selectivity towards 2-TBP during reaction time and increase in 4-TBP and 2,4-DTBP due to isomerization and dialkylation of the initial product, respectively [3,20,24,52].