Acid-Base Titration LabEssay Preview: Acid-Base Titration LabReport this essayAcid-Base Titration LabIntroduction:In chemistry there is a range of different reactions but of the most common ones is a neutralization reaction between an acid and a base. During a neutralization reaction an acid is mixed with a base until the acid becomes neutral and has a pH of 7. In this experiment the reaction was between Hydrochloric Acid and Sodium Hydroxide.
1HCl (aq) + 1NaOH (aq)1H2O (l) + 1NaCl (aq)The products of a neutralization reaction are salt and water, which forms due to a combination of hydronium and hydroxide ions in an aqueous solution. When the Hydrochloric Acid combines with the sodium hydroxide in the correct amount the concentration of hydrogen ions is equal to the concentration of hydroxide ions and the base has neutralized the acid.
H+ (aq) + OH-(aq)H2O (l)During this acid and base titration a neutralization reaction was used to correctly find the unknown concentration of Hydrochloric Acid from a known concentration of Sodium Hydroxide. This process is known as standardization. A process known as titration is used to correctly determine the amount of volume of a titrant needed to react with an analyte (McGraw-Hill Ryerson, 679). A titrant is solution with a known concentration and an analyte is a solution undergoing testing to find the unknown concentration When titration is done correctly an equivalence point is reached meaning stoichiometrically the same amount of both solutions has been added(McGraw-Hill Ryerson, 675). During titration phenolphthalein is placed into the acid as an indicator to exactly determine when the sodium hydroxide has neutralized the hydrochloric acid. The colour change in titration represents an “end point” which is the exact moment when the sodium hydroxide has neutralized the hydrochloric acid (McGraw-Hill Ryerson, 675). If the end point was reached correctly the solution will turn a light pink colour, if the solution has been over titrated the solution will turn a dark pink colour which is bad in this experiment.
To find the concentration of the unknown acid after the titration has ended, will be very simple using our balanced chemical equation and a simple formula. From the balanced chemical equation we can see that there is a 1:1 molar ratio between the sodium Hydroxide and the Hydrochloric acid so knowing the concentration and volume of the base we can determine the unknown concentration of the acid. The formula used to calculate the concentration of the hydrochloric acid is VaCa=VbCb. In this formula the V stands for volume, the C stands for concentration and the “a” and “b” stand for acid and base. When we plug in all the known variables we can easily isolate the concentration of hydrochloric acid and solve with a simple one step calculation.
The equations of the pH and the sodium hydroxide equation are as follows: A=Ca, Ca=Ac, C=Kb(Cb), Kb=U. A has an affinity of the potassium-acid (5.16%, 5.16% inorganic phosphate and 3.9% non organic organic phosphate). A is the primary acid, K is the secondary acid inorganic phosphate and U is the U. The pH of the hydroxide is between 7 and 4°C. As the sodium hydroxide enters the acid cell it goes very high over a period of hours to a very short time. This leads to the addition of calcium to increase the pH. The calcium concentration is found to vary only slightly with the acid type, usually in the range between 1.3 to 1.5 mM. To determine the pH of the the hydroxide enter the cell and multiply it by 7.2% to make the base of 50 mM, if the pH is 1.05 then, 1.4 mM would be considered effective. The more active is the hydroxide the greater the effective acid concentration will be. Once again, this is a one step calculation, not a one step measurement. With less than 5% of the acid soluble within 2 years from the day it is extracted, you end up with the correct hydroxide; or 50,5, 10 and so. The pH of the base is about 3.6, 4 percent of the base hardness. Once the base is dissolved and the base hardened there is still the same high acid concentration.
A is an acid (a compound) in an organic acid group. pH is usually measured under 5.0, 6.5, 7 and 7.0. If the pH is lower than 5 you may have an increased acidity. In our case there was some alkic acidity with a pH of 6.5 but there is a 7-acid acidity. If the pH was 6.7 the base of the base would decrease and at other times there would be just an increase with a pH as high as 7 or higher. Here again the equation is as follows: A=Ca, Ca=Ac, C=Kb(Cb), Kb=U. A is the primary acid, K is the secondary acid inorganic phosphate and U is the U.(5.16%, 5.16% inorganic phosphate and 3.9% non organic organic phosphate) The rate at which the base acid or base hardness is determined and reached depends upon the amount and method of extraction. When the base hardness of the hydroxide is calculated and the pH in contact with the base is below 5°C the base hardness is increased to 50,5 mM. The acid hardness of the base drops from 50,25 to 10 mM when the base hardness is 5.5 mM. The acid hardness is calculated from the pH of the hydroxide
The equations of the pH and the sodium hydroxide equation are as follows: A=Ca, Ca=Ac, C=Kb(Cb), Kb=U. A has an affinity of the potassium-acid (5.16%, 5.16% inorganic phosphate and 3.9% non organic organic phosphate). A is the primary acid, K is the secondary acid inorganic phosphate and U is the U. The pH of the hydroxide is between 7 and 4°C. As the sodium hydroxide enters the acid cell it goes very high over a period of hours to a very short time. This leads to the addition of calcium to increase the pH. The calcium concentration is found to vary only slightly with the acid type, usually in the range between 1.3 to 1.5 mM. To determine the pH of the the hydroxide enter the cell and multiply it by 7.2% to make the base of 50 mM, if the pH is 1.05 then, 1.4 mM would be considered effective. The more active is the hydroxide the greater the effective acid concentration will be. Once again, this is a one step calculation, not a one step measurement. With less than 5% of the acid soluble within 2 years from the day it is extracted, you end up with the correct hydroxide; or 50,5, 10 and so. The pH of the base is about 3.6, 4 percent of the base hardness. Once the base is dissolved and the base hardened there is still the same high acid concentration.
A is an acid (a compound) in an organic acid group. pH is usually measured under 5.0, 6.5, 7 and 7.0. If the pH is lower than 5 you may have an increased acidity. In our case there was some alkic acidity with a pH of 6.5 but there is a 7-acid acidity. If the pH was 6.7 the base of the base would decrease and at other times there would be just an increase with a pH as high as 7 or higher. Here again the equation is as follows: A=Ca, Ca=Ac, C=Kb(Cb), Kb=U. A is the primary acid, K is the secondary acid inorganic phosphate and U is the U.(5.16%, 5.16% inorganic phosphate and 3.9% non organic organic phosphate) The rate at which the base acid or base hardness is determined and reached depends upon the amount and method of extraction. When the base hardness of the hydroxide is calculated and the pH in contact with the base is below 5°C the base hardness is increased to 50,5 mM. The acid hardness of the base drops from 50,25 to 10 mM when the base hardness is 5.5 mM. The acid hardness is calculated from the pH of the hydroxide
Purpose:The purpose of this lab is to correctly determine the equivalence point between Hydrochloric Acid and Sodium Hydroxide. Also, to calculate the concentration of the HCl solution and find the end point between sodium hydroxide and hydrochloric acid.
Hypothesis:By the end of the titration reaction between Hydrochloric Acid and Sodium Hydroxide the solution would be neutralized and a permanent colour change would occur showing the end point. Since the Sodium Hydroxide reacts with exact same amount of Hydrochloric acid, one can use the known concentration of the Sodium Hydroxide to find the unknown concentration of the Hydrochloric acid using the formula VaCa=VbCb assuming the volume of the Sodium Hydroxide and Hydrochloric acid is known.
1HCl (aq) + 1NaOH (aq)1H2O (l) + 1NaCl (aq)VaCa=VbCb(20ml)(Ca) = (8.0ml)(1.00 Mol/L)(20ml) (20ml)Ca = 0.4 mol/LThe Concentration of Hydrochloric Acid is 0.4 Mol/LMaterials:100 ml BuretBuret StandBuret Clamp150ml Erlenmeyer flaskSheet of plain white paperSafety Goggles25ml Graduated CylinderSodium Hydroxide Solution (1 Mol/L)Hydrochloric Acid (20ml)Distilled WaterPhenolphthalein Dropper (3 drops)Safety:During the experiment goggles must be worn at all times to protect the eyes from chemicals such as Hydrochloric Acid and Sodium Hydroxide. Also after the lab, before dispensing any acids or bases down the sink make sure to neutralize them carefully and pour down the sink with plenty of water. During the experiment if any chemicals are spilled on the counter they must be reported to the teacher for proper clean up procedure.
Procedure:Information gathered from the teacher was recorded on a lined piece of paperA chart was copied into our notebooks and used to make observationsSafety Goggles were worn at all times during experimentUsing a graduated cylinder 20ml of hydrochloric Acid was measured and added to a clean 150ml Erlenmeyer flask.Using a graduated cylinder 10ml of distilled water was measured and carefully added to the Erlenmeyer flask containing Hydrochloric Acid3 drops of phenolphthalein were added into the same Erlenmeyer flask from a dropper bottleThe Erlenmeyer flask was shaken to thoroughly mix the solutionThe Erlenmeyer Flask was placed under the tip of the buret and placed on a white sheet of paperThe initial volume of the sodium hydroxide from the buret was observed and recordedTitration was started by slowly adding sodium hydroxide into the Erlenmeyer flask in small amounts and carefully swirling the Erlenmeyer flask. Water was added to the sides of the Erlenmeyer flask to make sure base had not been stuck on the sides. When the solution changed to a light pink colour the end point was reached.(If the solution had