Acid Base Titration Lab Report

3mL of the liquid in each of the vials were added into cuvettes and measured in the spectrophotometer. Before each time point the photo spectrometer was zeroed using a cuvette with 3mL of distilled water. If any of the results were considered unusual the machine was zeroed again and the sample was retested. The results from the spectrophotometer test were recorded in a table. The experiment was repeated six times to gain a sample size of six.

These color changes indicate a chemical change, which show that a reaction had occurred. In the first step when o-vanillin and p-toludine, imine was formed. The color change from green to orange suggests that imine appears as orange colored. In the second step, the addition of sodium borohydride reduced the imine into another derivative, which was yellowish lime color. The solution turned clear when acids and anhydrides was added, which indicated the precipitate were dissolved.

Standard Sodium hydroxide solution is the alkaline solution that will be used to titrate with soda water as it is a common solution that can be easily found in an ordinary school laboratory. It is a strong base. Carbonic acid is a weak acid which will react with a strong base to form a basic (pH > 7) solution. When Phenolphthalein is added to Soda water, the resultant solution is colourless. After titration with a strong base (sodium hydroxide), the solution will turn to pink as the solution becomes

In this experiment rate of reaction with different reactants concentration: KI (0.010 M), KBrO3 (0.040 M), and HCl (0.10 M) will be observed. So, this is reaction between iodide and bromate ion under acidic conditions: 6 I- (aq) +BrO3-(aq)+ H+(aq)→ 3I2(aq) + Br-(aq)+ 3H2O The end of the reaction, will be determined by observing color change of solution. Thus, solution should shange color to blue.

The next instruction was to proceed to step 12 where two drops of 6M NH4OH and 0.5 mL of 1M K2CrO4 was added which caused the solution to turn orange. After the tube was centrifuged, a precipitate was not present. This step had chances of error due to a false positive. A false positive was described as a result that would indicate the presence of a substance that was not really in solution. Barium would be the cation that would be the false positive.

Dependent The time taken for the bluish -black color to fade away (color of Iodine solution mix with starch solution ). The rate of enzyme reaction Minutes (min) Table 1.1 – Table shows the controlled variables in the experiment variables Units Measures of controlled variables.

The equation of the reaction between sodium hydroxide and ethanoic acid is as follows: CH3COOH + NaOH → CH3COONa + H2O We can measure the end point of titration process and we can also measure the amount of reactants. The concentration of ethanoic acid in the vinegar can be determined through stoichiometric calculations, Using the values obtained from the titration, and also the chemical equation as a reference. Phenolphthalein indicator is used in this acid-base titration Equipment and materials:

Its pH is greater than 7 and turns red litmus paper into blue. Acid- base neutralization is done by adding an acid to a base or a base to an acid until the substance has equal hydrogen and hydroxide ions. This is used to determine unknown concentration of a

To identify the unknown acid. 4. To determine acid dissociation constant, Ka and pKa for the unknown acid. Introduction: Titration process is used in an acid-base experiment in order to determine the concentrations of solutions of acids and bases.

Experiment #7: Column Chromatography of Food Dye Arianne Jan D. Tuozo Mr. Carlos Edward B. Santos October 12, 2015 Abstract Column chromatography is the separation of mixture’s components through a column. Before proceeding with the column chromatography itself, a proper solvent system must be chosen among the different solvents. The green colored food dye is the mixture whose components are separated.

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 solution turned red when it reached the end point. The titration was continued for 10 seconds after a permanent red color was obtained. The volume of 0.1 M NaOH solution used was determined.

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

The mass of vinegar used during the experiment was 4.108 grams. It was determined that there were .003129 moles of CH3COOH in the vinegar sample. Using this information and the molar mass of CH3COOH, which was 60.05 g/mol, the mass of acetic acid in the vinegar was calculated: 4.Vinegar is a 5% aqueous solution of acetic acid. Since the mass of acetic acid within the vinegar was calculated as .18789 g in step 3, the percent of CH3COOH was calculated using the following equation: To calculate the percent error, the experimental value of 4.5% acetic acid in vinegar was subtracted by the theoretical value of 5% and divided by 5% to yield a percent error of 8.54%. The following is a copy of the calculations done using decimals: 5.The equivalence point of the titration curve measured in step 1 was 25.25 mL of NaOH.

That caused a new initial reading of NaOH on the burette (see Table1 & 2). The drops were caused because the burette was not tightened enough at the bottom to avoid it from being hard to release the basic solution for titrating the acid. The volume of the acid used for each titration was 25ml. The volume of the solution was then calculated by subtracting the initial volume from the final volume. We then calculated the average volume at each temperature.