PURPOSE To determine the amount of water of crystallization in one mole of a hydrated salt and its formula
IBDP-1 IBDP (2012-2014) INTERNAL ASSESSMENT COVER PAGE CHEMISTRY NAME OF STUDENT NAME OF TEACHER TITLE OF INVESTIGATION LEVEL - HL SL DATE - TOPIC - TIME (IN HOURS) - USE OF ICT (IF ANY) – DATA LOGGING GRAPH PLOTTING SOFTWARE SPREADSHEET DATABASE COMPUTER MODEL / SIMULATION CRITERIA ASSESSED DESIGN (D) DATA COLLECTION AND PROCESSING (DCP) CONCLUSION AND EVALUATION (CE) PURPOSE To determine the amount of water of crystallization in one mole of a hydrated salt and its formula. HYPOTHESIS Hydrates are inorganic ionic salts that contain a specific number of water molecules loosely attached as a part of their structure. The water is chemically combined with the salt in a definite ratio. In this experiment, the percentage composition of water can be calculated based on the masses of the anhydrous and hydrated salt. The chemical formula of this hydrate in general is CuSO4.XH2O. Thus the achieved result from this experiment should probably be x=5. Therefore copper sulphate should have a formula of CuSO4.5H2O. When it is heated
AIM: To verify that mass-mass relationships hold by measuring the amount of NaCl produced.
Ilyas Shaikh IBDP -1 MASS-MASS RELATIONASHIPS AIM: To verify that mass-mass relationships hold by measuring the amount of NaCl produced. HYPOTHESIS: The fundamental law of chemical reactions is the Law of Mass Conservation (or Conservation of Mass). The law states that the total mass of reactants must equal the total mass of products for a chemical reaction. EXPERIMENTAL SETUP AND BACKGROUND: . To perform a reaction using measured samples of reactants 2. To measure the mass of the products; 3. To note the mass - mass relationships for this reaction. APPARATUS REQUIRED: 250 cm3 beaker Bunsen burner Graduated cylinder Safety glasses Spatula MATERIALS REQUIRED: Solid Na2CO3 . M HCl solution PROCEDURE: . I measured the mass of a clean dry 250 cm3 empty beaker to the nearest 0.01 gram. 2. I transferred the Na2CO3 to the beaker using a spatula weighed out 3 grams of it. I measured the mass of the beaker and Na2CO3 to the nearest 0.01 gram and recorded it. 3. I calculated the moles of HCl required to consume the Na2CO3 . 4. I added the acid to my beaker slowly, observing any chemical and physical changes that occur. 5. I heated the beaker on the Bunsen burner to saturate the solution. 6. Next I placed my beaker in the hot air oven to allow excess liquid to evaporate. 7. When the dry
Paper Chromatography on Amino Acids IA
Chemistry IA: Paper Chromatography of Amino Acids Values of Controlled Variables Solvent: 12ml butan-1-ol, 3ml ethanoic acid, 6ml H2O Ruler: for measuring distances for Rf value has an uncertainty of ±0.1cm Time: The chromatograph was left to left to run for 1 hour and 25 minutes. Observations After developing the chromatogram by spraying it in a fume cupboard with a suitable dye and then drying it, several shades of purple dots formed on the chromatography paper. Results The chromatogram shown below shows 3 distinct purple spots. These spots are labeled from one to three. Processing Data Unknown sample number Distance moved by amino acid (±0.1cm) Distance from amino acid origin to solvent front (±0.1cm) Calculations Rf values (±0.20cm) 1 1.6 9.5 2.5/9.5 0.16 2 2.5 9.5 3.3/9.5 0.26 3 7.0 9.5 7.0/9.5 0.74 Calculating the Rf value would allow the relationship of the distance moved by the unknown amino acid to the distance moved by the solvent front to be calculated. Data table showing Rf values of the unknown samples After the Rf values for the unknown samples have been obtained, we can now compare it with actual Rf values of the actual amino acids used. The following table compares obtained values and actual values and the amino acids: Unknown sample number Rf values obtained Literature values Amino Acid 1 0.16 0.14 Lysine 2
Aim: To investigate the reaction between sodium bicarbonate powder and ethanoic acid and discover the concept of limiting reagents.
Introduction Aim: To investigate the reaction between sodium bicarbonate powder and ethanoic acid and discover the concept of limiting reagents. Variables Independent: Mass of sodium bicarbonate (NaHCO3) Dependent: Volume of carbon dioxide gas (CO2) Controlled: Ethanoic Acid (CH3COOH) Chemical Reaction NaHCO3 + CH3COOH = CH3COONa + H2O + CO2 Raw data table Mass of NaHCO3/g Volume of CO2 1st Trial (cm3 ) /+ 1 Volume of CO2 2nd Trial (cm3 ) /+ 1 Volume of CO2 3rd Trial (cm3 ) /+ 1 0.30 83 78 78 0.50 128 132 134 0.70 152 154 152 0.90 154 150 152 1.10 154 153 154 1.30 157 153 153 Qualitative observations As conical flask is swirled, tube containing NaHCO3 falls into the ethanoic solution. Large bubbles appear and the solution produces white foam. After a few minutes, bubbles stop appearing and solution in the conical flask turns clear. No heat or sound was observed. Processed data table Mass of NaHCO3/g Average Volume of CO2 (cm3) 0.30 80 + 3 0.50 131 + 3 0.70 153 + 1.0* 0.90 152 + 2 1.10 154 + 1.0* 1.30 154 + 3 *Because uncertainty starts with 1, therefore 2 significant numbers is necessary. Sample Calculations Calculating the average (83 + 78 + 78) cm3 3 = 79.66667 cm3 Rounded to two significant figures is 80 cm3 Calculating the uncertainty for my averages Calculated using residuals i.e. Largest residual is 83
Design lab - Acetylsalicylic acid (ASA) synthesis
Eva Chiesa 2112-006 INTERNAL ASSESSMENT Acetylsalicylic acid synthesis Name: Eva Chiesa Candidate number: 2112-006 Examination session: May 2013 School: The English International School of Padua School number: 2112 Aim The aim of the experiment is to produce a sample of acetylsalicylic acid. Introduction Aspirin is thought to work by preventing a particular enzyme being formed at the site of the pain. This enzyme is involved in the synthesis of prostaglandins which are the ones that produce fever and inflammation, and the transmission of pain from the site of the injury to the brain. Aspirin causes many side effects, the most common is that it causes bleeding in the lining of the stomach. Exceeding the safe dosage can be fatal as the salicylic acid leads to acidosis due to a lowering of the hydrogen ion concentration in the blood.[1] Aspirin’s structure is as follows: The reaction that will occur is the following: (CH3CO)2O + HOC6H4COOH CH3CO2C6H4CO2H + CH3COOH acetic anhydride salicylic acid acetylsalicylic acid acetic acid Apparatus . Salicylic acid 2. Acetic anhydride 3. Sulphuric acid 4. Water 5. Distilled water 6. Ethanol 7. Weighing boat 8.
Experiment: Analysing molar mass of Aspirin
Experiment: Analyzing molar mass of aspirin Introduction In 1899 the Bayer Company of Germany introduced the ethanoate ester of salicylic acid naming it, ‘Aspirin’. Aspirin is an acid, it can be titrated with a base such as sodium hydroxide to the equivalence point. The following chemical equation describe the acid-base reaction that will be observed in this experiment. H-Aspirin + NaOH ------> Na-Aspirin + H2O (acid) (base) (salt) The above chemical equation is balanced as written. An indicator will be used to provide a way to visually determine the endpoint of the titration. Phenolphthalein changes from colourless to a faint pink while bromothymol blue changes from yellow to a faint blue at a pH of around 8. Aim To calculate the molar mass of Aspirin Hypothesis The chemical formula of Aspirin is C9H8O4. It can also be written as C6H5(OCOCH3)COOH. In this experiment, Aspirin, which is an acid, will react with sodium hydroxide, NaOH in an acid-base reaction to produce salt and water. This analysis makes use the fact that aspirin is a monoprotic acid and therefore reacts with NaOH according to the equation: C6H5(OCOCH3)COOH + NaOH ------> C6H5(OCOCH3)COO+Na- + H2O (acid) (base)
The purpose of this experiment is to determine the concentration of a solution of sodium hydroxide by titration against a standard solution of potassium hydrogen phthalate.
Aim The purpose of this experiment is to determine the concentration of a solution of sodium hydroxide by titration against a standard solution of potassium hydrogen phthalate. Qualitative Data . Sodium hydroxide solution is colorless before titration 2. HCL is colorless before titration 3. The end result of the solution is slight pink 4. When the solution is off-shot the solution has a deep purple color 5. before reaching the endpoint the solution turns pink and then fades away as we swirl the conical flask 6. the color of phenolphthalein is colorless before titration 7. the color of phenolphthalein is slight pink after titration 8. a drop of the solution is left behind in the pipette 9. ideal color of the solution is fade pink Quantitative Data Table below shows the various volumes of chemicals that where used from their respected apparatus Apparatus / Chemicals used Reading taken from the apparatus Pipette solution (±0.06 cm3) 25 cm3 Burette solution (±0.02 cm3) 50 cm3 Phenolphthalein indicator 2 drops Standard C8H5O4K solution (±0.12 cm3) 250 cm3 Mean volume tittered 25.54cm3 Table below shows the number of trials taken from the NaOH solution from the burette and the intial and final values of the solution titrated No of Titration Trials (burette) Initial reading (±0.02ml) Final reading (±0.02ml) 1 0.09 ml 25.70 ml 2 0.1 ml
Enthalpy of Combustion of Alchohols
Experiment 3: Enthalpy of Combustion of Alcohols ________________ Combustion of Ethanol Reaction: C2H5OH (l) + 3O2 (g) --> 2CO2 (g) + 3H2O (g) Raw Data Processed Data Mass of empty spirit lamp: 38.227 ± 0.001 grams Mass of ethanol: 54.408 – 38.227 = 16.181 ± 0.002 grams Mass of spirit lamp + ethanol: 54.408 ± 0.001 grams Mass of ethanol burnt: 54.408 – 51.283 = 3.125 ± 0.002 grams Final mass after burning: 51.283 ± 0.001 grams Rise in temperature: 40 – 27 = 13 ± 1°C Volume of water = 100 ± 0.5 ml Mass of water: 100 x 1 = 100 grams Initial Temperature = 27 ± 0.5°C Final Temperature = 40 ± 0.5°C Time elapsed: 7 minutes To find the energy transferred to the water, we can use this equation: Energy = 4.18 x 100 x 13 = 5354 Joules Mass of ethanol ÷ Molar mass of ethanol 3.125 g ÷ 46.06844 g/mol 0.0678 moles Assuming that all the heat is transferred to water, the calculated enthalpy of combustion of ethanol is: = 80,147.49263 Joules/mol 80 kJ mol-1 Error Propagations Uncertainty in mass: Uncertainty in measuring cylinder: Uncertainty in temperature: Total uncertainty: 0.064 + 7.69 + 0.5 = 8.254% Uncertainty in enthalpy value: 8.254% of 80 kJ/mol = ± 6.6032 kJ/mol The percentage error compared to literature value: The standard enthalpy change of combustion of ethanol (with uncertainty) is: -80 ± 6.6032 kJ mol-1
Enthalpy of Weak Base and Acid
Experiment 2: Enthalpy of Neutralization of Weak Acid with Weak Base ________________ Weak Base: Ammonium Hydroxide (NH4OH) Weak Acid: Acetic Acid (CH3CO2H) Reaction: NH4OH (aq) + CH3CO2H (aq) --> CH3COONH4 (aq) + H2O (l) Time (s) (±0.05s) Temperature (°C) (±0.05°C) Trial 1 Trial 2 Trial 3 Average Before adding base Initial Temperature 23 23 23 23 60 23 23 23 23 120 23 23 22.5 22.8 180 23 22.5 22.5 22.7 240 22.5 22.5 22.5 22.5 300 22.5 22.5 22 22.3 After adding base Peak Temperature 26.5 27.5 27.5 27.2 360 26 27 27 26.7 420 26 27 27 26.7 480 26 27 26.5 26.5 540 25.5 26.5 26.5 26.2 600 25.5 26.5 26.5 26.2 Uncertainty in Stopwatch = ± 0.05s Least count of Thermometer = 1oC Uncertainty in Thermometer = 0.5oC Volume of Acid Taken = 10 ml Volume of Base Taken = 10 ml Least count in Measuring cylinder = 1ml Uncertainty in measuring cylinder = ± 0.5ml Molarity of Acid = 1M Molarity of Base = 1M Processed Data To find enthalpy we can use this equation: Where E = Energy transfer between system and surroundings m = Mass of Substance c = Specific Heat capacity of substance ∆T = Change in Temperature Volume of solutions cup (Salt + Water) after reaction = 10ml (± 0.5ml) + 10ml (±0.5ml) = 20ml (± 1ml) Density of water is 1 g/ml. Therefore mass
Design -How does the surface area of Calcium carbonate (CaCO3) affect the rate of reaction with dilute hydrochloric acid (HCl)?
Horizon International School School code: 006048 Session: May 2013 Candidate name: Zwe Kyaw Zwa Candidate number: 006048-004 Session number: 60101 Subject level: Higher Level Assessment D DCP CE DESIGN Research Question How does the surface area of Calcium carbonate (CaCO3) affect the rate of reaction with dilute hydrochloric acid (HCl)? Variables Independent Variable: Size of Calcium carbonate Dependent Variable: Volume of Carbon dioxide produced Controlled Variables: Temperature Pressure Concentration of dilute hydrochloric acid Mass of Calcium carbonate Time interval Background and Theory To determine the effect of surface area on the rate of reaction, a known mass of calcium carbonate granules and powder are each placed in a flask, into which standard dilute hydrochloric acid is added. An acid reacts with a carbonate to give a chloride, water and carbon dioxide. Over time, the mass of calcium carbonate decreases while the volume of gas, carbon dioxide, increases. The more gas that is produced in the reaction, the faster the reaction is occurring. This can be measured by means of a graduated gas syringe. The reaction can be represented by the equation: CaCO3(s) + 2HCl(aq) CaCl2(aq) + H2O(l) + CO2(g) The results of the two reactions are plotted on the same axes of a graph of volume of CO2 produced against the time taken.