Experiment: Titration Aim My aim is to find the volume of hydrochloric acid needed to neutralise sodium hydroxide.
Experiment: Titration Aim My aim is to find the volume of hydrochloric acid needed to neutralise sodium hydroxide. Theory Titration is a laboratory method used to analyse a chemicals concentration. In this experiment 10cm3 of sodium hydroxide should be neutralised by 10cm3 of hydrochloric acid. Phenolphthalein is used in this experiment as an indictor where the base is a pink colour and acid as a cloudy white colour. When they are use to neutralise each other the mixture goes clear at the endpoint. The endpoint is where the number of moles in both solutions is equal. Different types of titration: * Acid based titration - neutralisation between an acid and a base * Redox titration - form of oxidation reduction * Complexometric titration - used to find certain ions Equipment The equipment I am going to use in this experiment; * Funnel * Hydrochloric acid * Sodium hydroxide * Bosshead / clamp * Stand * Conical flask * Burette * White tile * Goggles * Measuring cylinder * Phenolphthalein Funnel Diagram Bosshead / clamp Burette stand Sodium hydroxide Phenolphthalein White tile measuring cylinder hydrochloric acid Conical flask Method . First I have to collect the equipment, Funnel, hydrochloric acid, sodium hydroxide, bosshead / clamp, stand, conical flask, burette, white tile, goggles, measuring cylinder and
Titration Lab Report
CHEMISTRY LAB Titration Curves of Strong and Weak Acids and Bases Processing the Data: Questions: . Examine the time data for each of the Trials 1-4. In which trial(s) did the indicator change color at about the same time as the large increase in pH occurred at the equivalence point? In which trial(s) was there a significant difference in these two times? In all the 4 trials, the time taken for color change and the time taken for a large increase in pH was the same, leaving no significant difference between the two values. 2. Phenolphthalein changes from clear to red at a pH value of about 9. According to your results, with which combination(s) of strong or weak acids and bases can phenolphthalein be used to determine the equivalence point? The combination of a Strong Acid and Base will give us the equivalence point: there will be a color change of phenolphthalein at pH 9. It is also observed that the reaction between a Weak Acid and Strong Base can be used to obtain a pH of 9. 3. On each of the four printed graphs, draw a horizontal line from a pH value of 9 on the vertical axis to its intersection with the titration curve. In which trial(s) does this line intersect the nearly vertical region of the curve? In which trial(s) does this line miss the nearly vertical region of the curve? For Trials 1 and 3, the horizontal line from pH 9 intersects the S curve. For
Objective:-To prepare a buffer solution and observe the properties of a buffer
Experiment E5 Preparation and Properties of a buffer Date: 23.3.2011 Name: Leung She Ting Cherry Class: 6A 20 Objective To prepare a buffer solution and observe the properties of a buffer Introduction Buffer is a solution that can resist dramatic pH change when a small amount of acid or alkali is added to it. It is made up of equal amount of a weak acid/alkali and its conjugate base/acid. The working principle of buffer can be demonstrated as below: Ethanoic acid is a weak acid that undergoes slight dissociation, CH3COOH (aq)+H2O(l) CH3CHCOO-(aq) + H3O+(aq) where the equilibrium position mainly lies on the left side. At the same time, sodium ethanoate undergoes complete dissociation, CH3COONa (aq) CH3COO- (aq) + Na+ (aq) in which its equilibrium position lies mainly on the right side. When a small amount of acid is added to the solution, the addition of H3O+(aq) will shift the equilibrium of CH3COOH (aq)+H2O(l) CH3CHCOO-(aq) + H3O+(aq) to the left. The increase of [CH3COOH] does not cause a significant change in pH, thus the pH of the solution is kept almost constant. On the other hand, if a small amount of base is added to the solution, CH3COOH(aq) will react with the base, giving out salt i.e. CH3COONa. This shifts the equilibrium of CH3COONa (aq) CH3COO- (aq) + Na+ (aq) to
Thermometric Titration.
Thermometric Titration Aim To follow the titration and to find the endpoint by measuring the temperature changes take place during the titration. The importance of temperature in the experiment implies there is a connection with heat therefore the experiment is exothermic. Thus the products are at a lower energy level than the reactants so the energy has been given The acid and alkali we will use is sodium hydroxide and Hydrochloric acid. Background If an acid solution is added to an alkaline solution they will react and neutralize each other, forming a salt. The general Formula for this reaction is Acid + Base Salt + Water However, the resulting solution will be neutral only if acid and alkali are present in exactly the right quantities. If there is more acid than alkali, the all though all the alkali will be neutralized the solution will remain acid. On the other hand if there is more alkali than acid the solution will remain alkali. The precise volumes of acid and alkali solutions will neutralize each other out exactly. In a titration there is always one solution of accurately known solution, containing a known substance with an unknown concentration, is placed in a conical flask. The result from the titration is used to calculate the amount of substance present in the solution in the conical flask. Prediction I predict that as more of the acid is added to
Reaction between calcium carbonate and hydrochloric acid
the reaction between calcium carbonate and hydrochloric acid AIM- My task is to investigate the reaction between calcium carbonate and hydrochloric acid, which produces calcium chloride, carbon dioxide, and water. To do this I will conduct an experiment. Word Equation: Calcium + Hydrochloric Calcium + Carbon Dioxide + Water Carbonate Acid Chloride Chemical Equation: CaCo3 (s) + 2Hcl (aq) CaCl2 + Co2 (g) + H20 (l) The key variables in this experiment that affect the rate of reaction is, surface area, temperature, mass of CaCo3 and concentration of acid. The surface area can be investigated by increasing or decreasing the surface area of the calcium carbonate (marble) chips (i.e. have them as chips or powdered). The temperature can be investigated by increasing the temperature of water in the water trough. Increasing or decreasing the mass of the calcium carbonate chips used in the experiment can investigate the mass. The concentration can be investigated by increasing or decreasing the concentration of acid put on the marble chips. The variable I will be changing in order to conduct my experiment is the concentration of acid as this will have an effect on how much Carbon Dioxide is produced. There are a number of ways in which this experiment can be conducted. Firstly, the volume of Carbon
Communicating Laboratory Procedures
Communicating Laboratory Procedures (Nmsu, 2008) Laboratory procedures and practices must be communicated in a laboratory, because to keep the risk as minimum as possible by storing the chemical products in an appropriate and safe manner. A staff member shall be responsible for all stored chemicals and their use. All products must be labelled so that the researcher can identify and communicate the identity of the sample for laboratory staff. Unidentified chemical should be treated as infectious and disposed of in a proper way. All chemicals should be stored in suitable containment appropriate to hazard the agent. Containers used for storage must be enclosed or sealed. Accurate inventory should be maintained for the purpose of assessing risk and reducing unnecessary handling. Inventory must be updated to a minimum, annually. Each chemical container must also be labelled with the name or code of the chemical, the name and contact information of the user. This information must be legible to the environment is stored, i.e. indelible. A laboratory to reduce the risk good sanitation is essential to protect the integrity and chemicals. Cleaning routine should be invoked to provide work areas free from significant sources of contamination. It should be clean-up actions based on the higher degree of risk to the safety of individuals and the pilot may be exposed. Laboratory staffs
The Life of Garibaldi
nge and record how many drops you used. · Get the clamp ready and place the tile on the clamp, then place the conical flask on the tile. Rinse your burette with your diluted HCl to replace any previous liquids which may intervene in the results. Now secure the burette to the clamp making sure the nozzle is facing in the conical flask. You should now have your apparatus set-up like this: 30/5230/35230/image006.gif"> Funnel Burette filled with diluted HCl Conical Flask Clamp Tile Ca(OH) and Indicator · Now everything should be ready. From your volumetric flask, empty out the diluted HCl into a normal beaker. Using this beaker fill the burette up to the 0 mark with a funnel. · Start titrating slowly until the solution has totally reacted. Then record the results noting how much HCl you used. Record the results in a suitable format and repeat the experiment at least three more time for more accuracy. Finally record the average (mean) titre. · SAFTEY: this is extremely important as you are handling hydrochloric acid. Goggles must be worn at all times, hair must be tied back and bags must remain under the desk. If anything goes wrong, consult the teacher immediately. Always remember to work safely as HCl can be hazardous to your skin, the indicator may stain your clothing as well. (Accuracy): The pipette, burette and volumetric flask only have a percentage
To determine enthalpy change of hydration of magnesium sulphate(VI)
Chemistry Lab report ) Experiment No: 8A 2) Objective: To determine the heat of formation of calcium carbonate. 3) Date: 26th Nov, 2010 4) Theory: The experiment consists of 2 parts: a) In the 1st part, an accurately weighed known mass of calcium is added to a given dilute hydrochloric acid. During the addition, the following occurs: Ca(s) + 2H+(aq) --> Ca2+(aq) + H2(g) With the help of the data of heat change of the solution mixture, the average heat evolved by one mole of calcium during the reaction can be calculated. b) In the 2nd part, an accurately weighed known mass of calcium carbonate is added to a given dilute hydrochloric acid. During the addition, the following occurs: CaCO3(s) + 2H+(aq) --> Ca2+(aq) + CO2(g) + H2O(l) With the help of the data of heat change of the solution mixture, the average heat evolved by one mole of calcium carbonate during the reaction can be calculated. After that, by using a suitable energy-cycle diagram, and applying Hess's law, the heat formation of formation of calcium carbonate can be calculated. 5) Procedure: Please refer to the lab. manual 6) Data: 1st Part: Reaction of calcium with dil. Hydrochloric acid Experiment No: 2 Mass of Ca used / g 0.53 0.51 Volume of hydrochloric acid used: 100cm3 2nd Part: Reaction of calcium carbonate with dil. Hydrochloric acid Experiment No: 2 Mass of CaCO3 used / g 2.13
Objective: The purpose of this experiment is to determine the composition of a mixture of solutions of NaOH and Na2CO3 by double indicator method.
Experiment 4: Acid-base Titration using Method of Double Indicators Date: 2010/10/7 I. Objective: The purpose of this experiment is to determine the composition of a mixture of solutions of NaOH and Na2CO3 by double indicator method. II. Introduction: Consider a mixture of NaOH(aq) and Na2CO3(aq). Reaction between HCl(aq) and Na2CO3(aq) takes place in two stages: HCl(aq) + Na2CO3(aq) › NaHCO3(aq) + H2O(l) -------------------------(1) HCl(aq) + NaHCO3(aq) › NaCl(aq) + CO2(g) + H2O(l) -----------------(2) While that between HCl(aq) and NaOH(aq) completes in only one step: HCl(aq) + NaOH(aq) › NaCl(aq) + H2O(l) -----------------------------(3) The hydrochloric acid is placed in the in the burette and is added, slowly and with constant swirling, to the mixture of NaOH(aq) and Na2CO3(aq). Solution mixture of reaction (1) at the equivalence point is alkaline, while that of reaction (2) is acidic and that of reaction (3) is neutral. Therefore the whole titration should have three breaks in the pH curve, corresponding to the above three stages. Reactions (1) and (3) can be indicated by phenolphthalein and that of reaction (2) can be indicated by methyl orange. III. Procedure: . All apparatus should be rinsed properly with corresponding solution 2. 25cm3 of the mixture of NaOH(aq) and Na2CO3(aq) was pipetted into conical flask. 3. Burette was filled with
Analysis of 2 commercial brands of bleaching solution & a determination of the best buy
EXPERIMENT ( 2 ) Topic : Analysis of 2 commercial brands of bleaching solution & a determination of the best buy Introduction : Sodium chlorate(I) forms the basis of most commercial bleaches. The amount present in bleaching solution can be determined by a volumetric technique. In this experiment, sodium chlorate(I) reacts with excess potassium iodide in the presence of acid to liberate. The iodine is titrated against standard sodium thiosulphate solution. Chemicals : Bleach solution , 0.1 M Na2S2O3 ,1 M H2SO4 , KI , Starch indicator Procedures : 1. Determine the total volume of bleach in the commercial bottles provided. Note the brand name, volume & price of each sample. 2. Pipette 25 cm3 bleach solution into a 250 cm3 volumetric flask. Make up to the mark & mix well. 3. Pipette 25 cm3 of this solution into a conical flask. Add 10 cm3 KI solution & 10 cm3 1 M sulphuric acid. 4. Titrate this mixture against the standard sodium thiosulphate solution provided. Add starch indicator when the solution become pale yellow. 5. Record your results and calculate the molarity of the orginal bleach solution. 6. Determine which bleach has the lowest price per mole of actual bleach. Results : Brand A = ___________KAO_____________ Brand B = _________Best Buy____________ Volume = ___________1.5L______________ Volume = ____________2L_______________ Price = _______$12.9 /