Equivalence Point In An Acid-Base Titration
Discussion:
End point in this acid-base titration experiment refers to the point where the chemical reaction has reached its conclusion and no additional titrant should be added. The end point of this experiment can be obtained when the indicator used changes colour. For example colourless to light pink when phenolphthalein is used and red to orange and subsequently yellow when methyl orange is used.
Equivalence point, also known as stoichiometric point in an acid-base titration refers to the point where the reacting acid and base is in equal proportions. In the graph plotted, pH against volume of NaOH, the graph becomes nearly vertical at the equivalence point. The equivalence point also indicates that all the initial reactants have been
…show more content…
The pKa of this unknown weak acid is 4.0 and the Ka is 1.0 x 10-4 mol dm-3 while the molecular weight is 166.67 g mol-1. It is closely related to the ascorbic acid with a pKa of 4.10 and a Ka of 7.9 x 10-5 with a molecular weight of 176.12 g mol-1. Therefore it can be concluded that the unknown acid is ascorbic acid.
Titration technique is best suited for this experiment because the end point and equivalence point can be distinguished by the physical changes which are the colour change of the mixture. We are also able to better control and determine the volume of NaOH in the burette needed to neutralise HCI, CH3COOH and the unknown acid. This is because the amount of NaOH droplet can be altered when a burette is used thus, the NaOH solution can be dripped per drop at the time nearing the end point of the experiment as the colour changes rather quickly from light pink to pink.
Conclusion:
In conclusion, titration is an effective technique to determine the equivalence point, pH range, pKa, Ka and molecular mass of the unknown acid of the acid-base reaction. This technique is dependent on the colour change of the indicator which makes it easier to determine the end point of the experiment. Postlab Exercises:
1. Please refer to results and
Procion Red Dye Lab Report
1454 Words | 6 PagesA hot plate was placed under the ring stand. 50 mL of 3.0 M NaOH in a 250 mL beaker and a stir bar was placed in the beaker. The beaker with NaOH was placed on the hot plate and 3.75 grams of NaAlO2*5H2O was placed in the beaker. The temperature probe was placed in the beaker with the solution, not touching the bottom of the beaker. The solution was heated and stirred till the solution dissolved.
6.03 Pre Lab
993 Words | 4 PagesQuestion 4: List the 3 errors; • Adding too many drops of NaOH at the same time would affect the results because we can’t determine the exact equivalent point when the color changed. The results won’t be accurate and that will affect all the data that are dependent on the amount of NaOH to titrate. • Other error could be the hardness to notice a color change; we always use a white paper under the flask to determine when the color changes right away. And if we don’t use the white paper it will be hard to determine the color change and the amount of NaOH that was used to titrate it. • Also other source of error could be by not rising the burette with NaOH before we fill up with it, or it maybe they were rinsing it with a lot of NaOH which could affect the data recording for NaOH amount of titration.
Chemical Equation For The Presence Of Sodium Bicarbonate
795 Words | 4 PagesSodium Bicarbonate mixed with Hydrochloric acid. The chemical reaction observed showed that there was fizzing and bubbling, this is evidence that a new gas was being produced. This new gas, CO2 was generated from the reaction. After the fizzing stopped a liquid was leftover leading me to conclude the liquid leftover leading me to conclude the liquid leftover was the NaCl and H2O 4. You found a sample of a solution that has a faint odor resembling vinegar (an acid).
Unknown White Compound Lab Report
1367 Words | 6 PagesAbstract: The purpose of this experiment was to identify given Unknown White Compound by conducting various test and learning how to use lab techniques. Tests that are used during this experiment were a flame test, ion test, pH test, and conductivity test. The results drawn from these tests confirmed the identity of the Unknown White Compound to be sodium acetate (NaC2H3O2) because there were no presence of ions and sodium has a strong persistent orange color. The compound then will be synthesized with the compounds Na2CO3 and HC2H3O2 to find percent yield.
Essay On Soda Water Titration
1337 Words | 6 PagesStandard 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
Bio Chem: Lab Report Of Amylase In Enzyme
916 Words | 4 PagesIn test tube E, a colourless colour formed. It is because redox reaction occurred during the test. Idoine reduced into idoine ion ， which changre from brown to colourless. In test tube F, the iodine solution change from brown to purple . It is because the salt has a function of cofactor which will shorten the time for amylase to take to break down the
How Does Acid Rain Affect Plant Growth
1186 Words | 5 PagesIntroduction: In this task I will be researching the effect that acid rain has on the rate of plant growth. Acid rain is any type of precipitation with a high pH, with high levels of nitric acids. The reason why I had chosen this topic was because acid rain seems to have a great effect on the effect of plant growth, and plants play a very important role in our ecosystem. Acid rain is a major problem in our environment when we are not able to neutralize the acidity.
Determination Of Ethanoic Acid In Vinegar Lab Report
1489 Words | 6 PagesThe 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:
Acid Base Neutralization Lab Report
1001 Words | 5 PagesIts 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
Lab Report On Acid Base Titration
1346 Words | 6 PagesTo 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.
Enthalpy Of Neutralization Lab Report
1054 Words | 5 Pagesn=cV n=1.00 mol dm^(-3)×(25 dm^3±0.16%)/1000=0.025 mol±0.16 % The enthalpy of neutralization is then calculated. ∆H=(-1356.5 J±3.104% )/(0.025 mol±0.16%)=-54260 J 〖mol〗^(-1)±3.3 % ∆H=-54260 J m〖ol〗^(-1)±3.3%÷1000=-54 kJ 〖mol〗^(-1)±3.3 %
Analysis Of Phosphoriic Acid In Soft Drinks
1982 Words | 8 PagesBuffer solutions of pH 4 and 7 6. Graduated cylinder - 100 mL 7. Volumetric flask with stopper - 250 mL 8. Two 100-mL beakers 9. Two 50-mL Burettes 10.
CH3COOH And Naoh Lab Report
1052 Words | 5 PagesIntroduction Strong acids and strong acids both dissociate completely in water forming ions. However, strong acids donate a proton to form H3O+ along with a conjugate base and strong bases accept a proton to form OH- along with a conjugate acid. The chemical behavior of acids and bases are opposite. When they are together, their ions cancel out and form a neutral solution. In this experiment, HCl and NaOH will react to form NaOH and H2O with these two steps: The overall reaction is: Both Na+ and Cl- ions combine to form NaCl.
Benzoic Acid Lab Report
767 Words | 4 PagesThat 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.
Lifebuoy Marketing Strategy
1447 Words | 6 PagesThis carbolic acid is what gives Lifebuoy the distinctive red colour and the strong medical
More about Equivalence Point In An Acid-Base Titration
Procion Red Dye Lab Report
1454 Words | 6 Pages6.03 Pre Lab
993 Words | 4 PagesChemical Equation For The Presence Of Sodium Bicarbonate
795 Words | 4 PagesUnknown White Compound Lab Report
1367 Words | 6 PagesEssay On Soda Water Titration
1337 Words | 6 PagesBio Chem: Lab Report Of Amylase In Enzyme
916 Words | 4 PagesHow Does Acid Rain Affect Plant Growth
1186 Words | 5 PagesDetermination Of Ethanoic Acid In Vinegar Lab Report
1489 Words | 6 PagesAcid Base Neutralization Lab Report
1001 Words | 5 PagesLab Report On Acid Base Titration
1346 Words | 6 PagesEnthalpy Of Neutralization Lab Report
1054 Words | 5 PagesAnalysis Of Phosphoriic Acid In Soft Drinks
1982 Words | 8 PagesCH3COOH And Naoh Lab Report
1052 Words | 5 PagesBenzoic Acid Lab Report
767 Words | 4 PagesLifebuoy Marketing Strategy
1447 Words | 6 Pages