Norah Albaiz
CHMY143-016
Katie Link
Lab Partner: Lydia Aman
Standardization of Acids and Bases
Purpose:
The purpose of this experiment was to determine the unknown concentrations of NaOH, HCl, H2SO4, Ba(OH)2 by using a technique called titration. Titration is where the titrant is added from a buret to a known quantity of an analyte until the reaction is complete. Acid-base titration techniques can help determine the unknown concentrations of the analytes. Titrations also allow us to find the pH, knowing the pH of a substance is often a key method to regulate the quality of foods and other products produced for sale.
Primary standard solutions are made by the exact direct amounts of the mass of solute and the volume of solution. Whereas, secondary standard solutions are solutions with concentration that cannot be determined directly from the amount of solute and volume of solution, but the concentration is found by specific analysis of the solution itself. It is typically standardized against a primary standard. The qualifications of a good primary standard are to be very pure, unchanging, to have a high molecular weight, and not be sensitive to the environment.
Procedure:
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The KHP was dissolved in about 25 mL of water, 2 drops of phenolphthalein were added to the solution. A buret was rinsed three times with about 5 mL of NaOH, the buret was securely clamped to a ring stand. The buret was filled with NaOH solution to slightly above the zero mark. A waste beaker was placed under the apparatus and the stopcock was opened to run a small amount of solution out of the buret to remove any air bubbles from the stopcock. The initial volume on the buret was recorded. The stopcock was opened while the KHP solution was gently stirred. The solution turned faint pink, the stopcock was closed, and the final volume was recorded. The titration was
5. Question 5: a) As mentioned in the manual, we have the ratio (K/H+ ), if H+ was lower than K then the equivalent point will be achieved and it will change color. And if H+ was more than K then the solution we are titrating will be the same, the equivalent point won’t be achieved, and it will be acidic solution. And to find the value of H+ is by having the value of pH, therefore the pH has changed from 7 to 9, which is by shifting from 10-7 to 10 -8 by adding the 0.01 of the base, and it will shift again from 10 -8 to 10 -9 by adding another 0.01 of the base to the solution , the different that’s added between the two shifting are close to each other which indicates that the
Next, about 10 mL of both solutions, Red 40 and Blue 1, were added to a small beaker. The concentration of the stock solution were recorded, 52.1 ppm for Red 40 and 16.6 ppm for Blue 1. Then, using the volumetric pipette, 5 mL of each solution was transferred into a 10 mL volumetric flask, labelled either R1 or B1. Deionized water was added into the flask using a pipette until the solution level reached a line which indicated 10 mL. A cap for the flask was inserted and the flask was invented a few times to completely mix the solution. Then, the volumetric pipette was rinsed with fresh deionized water and
After obtaining an homogeneous mixture, the flask was placed in an ice bath during five minutes next to a graduated cylinder containing 5.0 mL of concentrated sulfuric acid. The temperature of the ice bath was recorded to be 1.1 °C. Likewise, a second graduated cylinder containing 1.8 mL of nitric acid and 2.5 mL of sulfuric acid was immersed in the cold ice bath to keep the three different solutions at the same temperature. Thereafter, the cold 5.0 mL of H2SO4 were added to the erlenmeyer flask containing the acetanilide solution, which remained in the cold water for approximately another 4 minutes.
Unit 7 Assignment Acid-Base Balance: Respiratory Acidosis and Alkalosis, Metabolic Acidosis and Alkalosis Tianna Robinson February 23,2016 SC131: Human Anatomy and Physiology Normal blood pH ranges from7.35 to 7.45. When blood pH decreases below 7.35 an acidosis occurs. Respiratory acidosis is caused when the lungs cannot remove all of the carbon dioxide that is produced by the body and body fluids become too acidic (Respiratory acidosis, 2014). Ranges that are normal for PaCO2 are 35-45 mm Hg.
Titrations are a technique used within modern industrial laboratories to measure the proportions of chemicals within a solution. It is a simple and useful method and due to its versatility it can be used within many areas and aspects of science industries to either develop or analyse key chemical compounds. Despite the preparation of standard solutions and the carrying out of titrations being the same in modern industrial laboratories, the methods in which they are carried out can differ. Different ways titrations and standard solutions can be carried out?
Distilled water was added to fill the flask to the 250-milliliter mark and the solution was mixed
Acid and base balance of body is normally strongly controlled, keeping the arterial blood pH between 7.38 and 7.42. Acid and base is also important in human homeostasis regarding the appropriate balance between acids and bases; this is also called pH. The body is very sensitive to its pH level, so strong mechanisms exist to maintain it. When pH is imbalanced the protein become denatured and digested, enzymes lose their ability to function, and can cause death. Metabolic Acidosis and Alkalosis: Metabolic Acidosis and Alkalosis are caused by an imbalance of acids or bases and their excretion by the kidneys. Metabolic acidosis produces when the amount of acid in the body is increased through absorption of a substance that can be broken down to an acid.
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:
Standardization of NaOH solution The prepared solution in part A was used to determine the acidity of the two different brands of soft drinks. But before it, the NaOH solution was standardized first. A 0.15 g of potassium acid phthalate was dissolved in 0.05 L of water in an Erlenmeyer flask. Afterwards, 3 drops of phenolphthalein was added.
Practical I: Acid-base equilibrium & pH of solutions Aims/Objectives: 1. To determine the pH range where the indicator changes colour. 2. To identify the suitable indicators for different titrations. 3.
D1 When someone is undergoing half-hour of extreme exercise the person needs to drink more to keep their acid-base balance. Human body contains largely water, starting from concerning 75 % of body mass. To keep the body healthy we need to exercise and have balanced diet. In balanced diet we should include carbohydrates, fats, proteins, vitamins and minerals. Good acid-base balance and blood pH levels supports: Cardiovascular system health Healthy cholesterol levels Healthy blood sugar balance Fat metabolism Weight loss Energy balance Proper cleansing and repair of tissues Diseases
The internal standard method allows a very accurate analysis to be performed, since the behaviour of the species of interest is compared to that of a known substance which is present in a specified amount. It is usual to include an identical volume or mass of the internal standard into each prepared standard. This facilitates easier calculations of the composition of the
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
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.