# Volumetric Analysis Lab

731 Words 3 Pages
The purpose and objective of this experiment was to determine the percent by mass of acetic acid within a sample of vinegar using volumetric analysis with the titration technique. The theory is that if the volume and molar concentration of the standardized sodium hydroxide (NaOH) solution is known, then the percent by mass of the acetic acid (CH3COOH) in vinegar can be calculated after a titration.1 Within this experiment, a NaOH solution was standardized with a primary standard acid of potassium hydrogen phthalate (KHC8H4O4) in order to determine the molar concentration of the NaOH solution.1 The standardized NaOH solution was then used to determine the moles, mass, and percent by mass of CH3COOH in a sample of vinegar. The vinegar used in the experiment was labeled as “Harry Potter”. The reported molar concentration of the NaOH solution was 5.42E-02 mol/L …show more content…
The experiment used volumetric analysis, in which a known quantity of a substance reacts with an unknown amount of another substance for an aqueous solution reaction.2 To standardize the NaOH solution and determine the molar concentration, it needed to react with a primary standard acid due to NaOH being hygroscopic, in which it readily absorbs water vapor.1 In this case, KHC8H4O4 served as the primary acid standard since it’s only slightly hygroscopic and the mass was known, in which the moles could then be calculated from using the equation: mass (g) KHC8H4O4 mol KHC8H4O4204.23 g KHC8H4O4= mol KHC8H4O4
The reaction occurs with the dispensal of the NaOH titrant from the buret into a flask containing the KHC8H4O4, which functioned as the analyte. The balanced equation for this reaction was:
KHC8H4O4 (aq) + NaOH (aq) → H2O (l) + NaKC8H4O4 (aq).
This indicates that there is a one-to-one mole ratio, in which one mole of KHC8H4O4 reacts with one mole of

• ## 1what Is An Acid-Base Titration?

The average of volume of NaOH used in the calculations was calculated as the average of the two best values which increases accuracy. The final pH of the titration can be altered if excess indicator is a added. Experiment 2: To prepare the solution of KIO3, the mass that must be added in 250 mL of distilled water must be calculated as shown; 1 mol of KIO3 is contain in 214.00g 0.005 mol of KIO3 1.07g Since the potassium iodate is only 99% pure 99% 1.07g 100% 1.081g Hence, mass of KIO3 used= 1.081g Apart from KIO3 and KI, sulfuric acid is also present in the conical flask, in excess, to provide H+ ions to increase the rate of reaction. 2.3 Conclusion After having done both experiment in the laboratory, we can conclude that he titration method relying on visual detection of the end point for quite precise determination of the unknown…

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• ## The Volumetric Analysis Experiment

The next titration with standard solution of NaOH with unknown concentration of HCl. The procedure is like previous titration of KHP with NaOH, but in this case instead of acid KHP we use hydrochloric acid. The HCl will react in one-to-one ratio with the base, so it will be easy to calculate the concentrations. The reactions follow: HCl (aq) + NaOH (aq) → H_2O(l) + NaCl…

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• ## Titration In Gastric Acid Essay

Determination of the Concentration of Acid in Gastric Juice Introduction Titration is a method where a solution of known concentration is used to find the concentration of an unknown solution. A standard solution is a solution of precisely known concentration. The aim of this experiment was to go over the use of pipettes, burettes, titrations and also to reinforce the concept of molarity. In this experiment, a titration was carried out using a standard solution of hydrochloric acid to establish the molarity of a solution of sodium hydroxide. The concentration of acid in the gastric juice sample was determined using that solution of sodium hydroxide.…

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• ## Thin Layer Chromatography

The 3M NaOH reacted with only the benzoic acid, causing it to produce sodium benzoate while the biphenyl remained the same. The manipulation of the aqueous pH level caused the organic acid and neutral compound to separate, but did not cause the layers to form. The sodium benzoate was soluble within the water (aqueous layer), while the biphenyl was soluble in the dichloromethane (organic layer). Due to Na2OH4 being highly soluble in water, it was used to absorb any water found in the organic layer. Using the equations and the numbers on Table 1 found in the data section, the Rf value for the isolated biphenyl was 0.66, the weight was 0.107 g, and recovery percentage was 35.7%.…

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• ## Phenolphthalein Chemistry Lab Report

To continue, a primary standard is a solution prepared by direct measurements of the mass of solute and the volume of solution, it has known quantitative data. However, a secondary standard solution is a solution whose concentration cannot be determined directly by weight of solute and volume of solution, the concentration must be determined by analysis or experimentation of the solution itself, as presented in ChemWiki. The purpose of titrating KHP with NaOH was to neutralize our experiment, or reach an endpoint as indicated by the phenolphthalein. Titration is used in order to find the concentration of a basic solution. The amount of reactants that have been mixed at the equivalence point depends on the stoichiometry of the reaction.…

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• ## Willow Tree Lab Report

Impurities in this experiment can result from incomplete acetylation of aspirin or hydrolysis of the aspirin during the isolation steps. The first test to determine the purity of the sample was to take the mass of the of acetylsalicylic acid product and compare it to the theoretical yield. The percent yield of the acetylsalicylic acid sample was 99.36% which indicates that the experiment was successful and followed the rules of chemistry. The second test to determine the purity of the sample was to mix 2.5% ferric chloride with a few crystals of acetylsalicylic acid product. The ferric chloride will create an iron-phenol complex with iron that causes a color change ranging from red to violet color.…

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• ## Phenolphthalein Lab Report

Phenolphthalein is often used as an indicator in acid base reactions. The reaction used in this lab is: C_20 H_14 O_(4 (aq))+46 NaOH_((aq))→46 Na_( (aq))^++20 H_2 CO_(2 (aq))+10 H_2 O_((l)). Phenolphthalein and sodium hydroxide react to form carbonous acid, water, and Na+ ions. This reaction is a neutralization reaction, where phenolphthalein, a weak acid, reacts with a strong base, sodium hydroxide. When phenolphthalein is put into a basic solution, it turns pink.…

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• ## Lab Report: Moolar Volume Of A Gas At STP

Dalton’s Law was relevant in this experiment because it can be used to find the partial pressure exerted by the hydrogen by itself. It was hypothesized that if a gas is created through the reaction Mg + HCl → MgCl2 + H2 at a constant pressure and temperature, then the molar volume can be found out using gas laws because gases have direct and indirect relationships that can be used to find the unknown characteristic of said…

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• ## Alkalinity Lab

Standardization of HCL. The titrant solution of 0.02 m HCL and 0.08 M NaCl is standardized using a solution consists of a mixture of 0.05 M Na2CO3 and 0.085 M of NaCl as analytic solution. 50 ml the latter solution is placed into a beaker and pH electrodes are immersed into the solution to read the electrode potential (mV). Two drops of indicator methyl orange are added to the solution. Detailed data is collected by adding small volume of acid titrant and recording the corresponding to the two equivalence points.…

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• ## Acid Base Titrations II: Potentiometric And Indicator T

Next, 25mL of 0.1 M Acetic acid is pipetted into a 100mL beaker. The 0.1 M Acetic acid is titrated with the 0.1 M NaOH in increments given in the data sheet; mixing well at each point and wait until the pH stabilizes. The pH is recorded at each increment and the electrode is rinsed with distilled water and placed back in the beaker with distilled water. Then, 25mL of 0.1 M Acetic acid is pipetted into a 250mL Erlenmeyer flask. Next, 2-3 drops of the proper indicator is added.…

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