...Braidon Berry Lab 4: Stoichiometry of a Precipitation Reaction Background: Stoichiometry is a challenging yet essential part of learning chemistry. By utilitizing the resources of this course, as well as the lab work. Learning this difficult section of the course can be done with hard work and sharp attention. Purpose: The purpose of this lab was to learn how to connect calculations with real life examples. Doing this lab while doing the calculations for the molarity and molar masses, made it more challenging, however it did help in seating the knowledge and connecting it to the course. Procedure: To start, the dry Calcium Chloride Dihydrate, was weighed out and mixed with a small amount of distilled water. After that step the molarity of the CaCl2 was determined and logged in the data sheet. Similar steps were followed in terms of measuring dry material, weighing it, and then mixing it with distilled water. This will be necessary in order to observe the reaction and calculate more. Then the water was now filtered in the paper filter, this filter would later be dried in the sunlight and weighed to measure the mass of the product. After the filtering was complete, the percent yield could be calculated, as well as the actual mass of the precipitate. Data: |Initial: CaCl2*2H20 (g) |1.0 g | |Initial: CaCl2*2H20 (moles) ...
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...Lab: STOIOCHIOMETRY OF A PRECIPITATION OF REACTION By: Ruth Pierre 6/1/15 PURPOSE Stoichiometry is a section of chemistry that involves using relationships between reactants and products in a chemical reaction to determine desired quantitative data. Stoichiometry means the measure of elements. In order to use stoichiometry it is important to understand the relationships that exist between products and reactants and why they exist, which require understanding how to balanced reactions. The purpose of this experiment is to predict the amount of product produced in a precipitation reaction using stoichiometry. This experiment will also to determine the actual yield versus the theoretical yield in order to calculate the percent yield. MATERIALS * Distilled water * Paper towels * Small paper cup * Coffee cup or mug * Beaker 100 ml glass * Funnel * Cylinder 25 ml * Goggles for safety * Scale Digital-500g * Weighing boat plastic * CaCl2·2 H2O-Calcium Chloride, Dihydrate - 2.5 g * Filter Paper 12.5-cm, Na2CO3 -Sodium Carbonate - 2 g PROCUDURE 1. Put on your goggles. 2. Weigh out 1.0 g of CaCl2·2H2O and put it into the 100-mL beaker. Add 25 mL of distilled water and stir to form the calcium chloride solution. Use only distilled water since tap water may have impurities that interfere with the experiment. 3. Use stoichiometry to determine how much Na2CO3 you will need for a full reaction. 4. Weigh the calculated...
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...Determining the Limiting Reactant and Percent Yield in a Precipitation Reaction Objectives: • Observe the reaction between solutions of sodium carbonate and calcium chloride. • Determine which of the reactants is the limiting reactant and which is the excess reactant. • Determine the theoretical mass of precipitate that should form. • Compare the actual mass with the theoretical mass of precipitate and calculate the percent yield. Materials: Balance 0.70 M sodium carbonate solution, Na2CO3(aq) Graduated cylinder 0.50 M calcium chloride solution, CaCl2(aq) Beaker (250 mL) Wash Bottle (distilled H2O) Filter paper Funnel Iron ring Ring stand Procedure: Part I: The Precipitation Reaction (Day 1) 1. Obtain two clean, dry 25 mL graduated cylinders and one 250 mL beaker. 2. In one of the graduated cylinders, measure 25 mL of the Na2CO3 solution. In the other graduated cylinder, measure 25 mL of the CaCl2 solution. Record these volumes in your data table. 3. Pour the contents of both graduated cylinders into the 250 mL beaker and observe the results. Record these qualitative observations in your observations table. Allow the contents of the beaker to sit undisturbed for approximately 5 minutes to see what happens to the suspended solid particles. Meanwhile, proceed to step 4. 4. Obtain a piece of filter paper and put your initials and your partner’s initials on it using a pencil. Measure and record the mass of the filter paper, then use...
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...UNIVERSITI TUNKU ABDUL RAHMAN Centre Course Year/ Trimester Lecturer : : : : Centre for Foundation Studies Foundation In Science Year 1 Trimester 1 Unit Code Unit Title Session : : : FHSC1114 Physical Chemistry 2014/05 Ms Azlina Banu, Mr Tam Yun Hong, Ms Chong Pui Kuan, Ms Amelia Chiang Kar Mun, Ms Farhanah, Ms Wong Jing Tyng, Ms Jamie Anne, Ms Lau Mei Chien, Mr Ng Sweet Kin, Ms Phang Ying Ning, Ms Precilla, Ms Rachel Tham, Ms Rajalakshmi, Mr Tan Jun Bin, Ms Tan Lee Siew Tutorial 3 : Chapter 3 Stoichiometry and Solution Concentration 1. Balance the following equations: (a) Al(s) + NH4ClO4(s) → Al2O3(s) + AlCl3(s) + NO(g) + H2O(g) (b) GaBr3(aq) + Na2SO3(aq) → Ga2(SO3)3(aq) + NaBr(aq) 2. Ethanol, C2H5OH, is a liquid with a density of 0.789 g ml-1 at 25 °C. Calculate the molarity of ethanol solution made by dissolving 20.00 mL of ethanol at 25 °C in enough water to make 250.0 ml of solution. [Ans: 1.37 mol L-1] 3. Copper sulfate is widely used as a dietary supplement for animal feed. A lab technician prepares a “stock” solution of CuSO4 by dissolving 79.80 g of CuSO4 in enough water to make 500.0 mL of solution. (a) Determine the molarity of the CuSO4 “stock” solution prepared by the technician. [Ans: 1 mol L-1] (b) Calculate the volume of CuSO4 “stock” solution that should be diluted to give 2.5 L of [Ans: 0.25 L] 0.1 M CuSO4. 4. Aluminum is a limiting reactant in the reaction with sulfur gas to form aluminum sulfide. Initially, 1.18 mol of aluminum and 2.25 mol of sulfur are...
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...Chapter Review (select your own) | 4 | Multistep conversionsQUIZ | * Mole Recipies * Mole Road Map index card * Have them pick what they want to bake and they get half a period to work on conversions and then the weekend to bake. Bring in milk for us to enjoy with our cookies. | 5 | Percentage Composition | Read pgs 258-261Chewing Gum LabDry Lab pg 260Pg 260 # 1-10 (even)Pg. 262 # 1-6 | 6 | Empirical Formula | Nut boltide labRead pgs 268-270Pg 270 # 7, 9, 12Read pgs 271-276Do # 31-40 (even) pg 275 | 7 | Combustion Analysis type problem and Hydrate Lab Prep | Pg 277 # 16, 17, 18 (Pre-lab) + data table for 3 hydrates | 8 | Mole Airlines flight 1023 | Work in groups of 4 and hand in at the end of the period with full calculations and ID chart filled outPg 225 # 41-47 (odd)Pg 278 # 51-60 (even)Pg 279 # 1-16 (all) | 9 | Problem Set on Empirical Formula and % Composition | Work in pairs and set up a solutions gallery with chart paper solutions in review for their quizQUIZ | 10 | Stoichiometry | Bicycle Activity – IntroRead pgs 296-299Pg 298 # 1-10 (odd)Pg 299 # 1-6 (even)Pg 300 # 11-20 (odd) | 11 | Chalk Lab | Activtiy 7.1 pg 301Mole MethodRead pgs 301-304 Pg 304 #21-30 (even)Pg 305 # 1, 4, 6, 7,10, 11 | 12 | Limiting Reagent Problems | Socratic – full step by step with a problemRead pgs 306-308Pg 309Do # # 31-39 (even) (practice)Do # 8, 10,...
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...CHAPTER 3 MASS RELATIONSHIPS IN CHEMICAL REACTIONS This chapter reviews the mole concept, balancing chemical equations, and stoichiometry. The topics covered in this chapter are: • Atomic mass and average atomic mass • A vogadro’ s number, mole, and molar mass • Percent composition calculations • Empirical and molecular formula determinations • Chemical equations, amount of reactant and product calculations • Limiting reagents and reaction yield calculations Take Note: It is absolutely essential that you master the mole concept to do well on the quantitative aspects of AP Chemistry!! When solving quantitative problems on the Free Response section of the AP exam, supporting work must be shown to receive credit. Using dimensional analysis is a very powerful technique in solving problems. Be sure to report your answer to the correct number of significant figures (see Chapter 1 in this review book). Atomic mass and average atomic mass Atomic mass is the mass of an atom in atomic mass units (amu). One amu is defined as 1/12 of one C-12 atom. The C-12 isotope has a mass of exactly 12.000 amu. The C-12 isotope provides the relative scale for the masses of the other elements. Average atomic mass is the value reported on the periodic table, which takes into account the various isotopes of an element and their respective frequencies. To calculate the average atomic mass of an element, add up the different masses of the isotopes (using amu) multiplied by each isotope’s abundance...
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...point of the product is not taken due to minimal product. In the second part of the reaction excess reagents are used and the synthesized product is in very small quantities. The product synthesized is diastereomers of 1-(4-nitrophenyl)-3-oxobutyl 3,3,3-trifluoro-2-methoxy-2-phenylpropanoate. The identity of this compound is confirmed by the following peaks seen in 1H NMR: 8.19 and 7.62 ppm, 5.47 ppm, 2.90, 2.13 ppm, 3.30 ppm, 7.36 – 7.38 ppm. The melting point, IR spectrum, theoretical yield or percentage yield is not found since all of it used in 1H NMR analysis. The product 1H NMR shows a mix of both the diastereomers, but it is difficult to ascertain which one is in excess. Introduction The aldol reaction that was experienced in this lab is the nucleophillic addition of an enolate to a carbonyl group to form a B-hydroxycarbonyl. This reaction is a very powerful method to construct of carbon-carbon bonds. Nature has developed the aldolase enzymes that catalyze biological aldol reactions. Aldolase is the enzyme that produces only one enantiomeric product that is hard to achieve. A simple amino acid L-proline can be used as the aldolase catalyst in asymmetric aldol reaction of acetone with a variety of aldehydes. This method produced 68% and 76% of...
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...Randall Elrod 12/6/2013 Acetaminophen Title Acetaminophen Purpose To prepare acetaminophen. Theory Acetaminophen is a synthetic, nonopiate, centrally acting analgesic derived from p-aminophenol.1 The full chemical name is N-acetyl-p-aminophenol.1 The pKa of acetaminophen is 9.51 at 25°C.1 Acetaminophen is used to relieve mild to moderate pain from headaches, muscle aches, menstrual periods, colds and sore throats, toothaches, backaches, and reactions to vaccinations (shots), and to reduce fever.2 Acetaminophen may also be used to relieve the pain of osteoarthritis (arthritis caused by the breakdown of the lining of the joints).2 Acetaminophen is in a class of medications called analgesics (pain relievers) and antipyretics (fever reducers).2 It works by changing the way the body senses pain and by cooling the body.2 Acetaminophen is one of the most commonly used medicines in the United States.3 When used according to the label directions, it has a well-established record of safety and efficacy.3 Although acetaminophen overdose is very rare in the context of its broad usage, overdose can be toxic and lead to acute liver failure.3 Preparation of acetaminophen involves treating an amine with an acid anhydride to form an amide.4 In this experiment, p-aminophenol (the amine) is treated with acetic anhydride to form acetaminophen (p-acetamidophenol), the amide. The chemical reaction for acetaminophen is as follows: 4 Procedure Procedure is as taken from Pavia,...
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...|Product | |(theoretical) |(theoretical) | |1,2-dibromo-1,2-diphenylethane |340.1g/mol |.496g |.00146 mol | #Only those part of the stoichiometic equation. |Product Data | |Mass |% Yield |Exptl MP |Literature MP | |.0852g |17.8 |220-237⁰C |240-243⁰C | Discussion In this lab bibenzyl was dissolved in a dichloromethane solution and then reacted with a 10%...
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...UNIVERSITI TUNKU ABDUL RAHMAN Centre Course Year/ Trimester Lecturer : : : Centre for Foundation Studies Foundation In Science Year 1 Trimester 1 Unit Code Unit Title Session : : : FHSC1114 Physical Chemistry 2015/05 : Ms. Amelia Chiang, Ms. Azlina Banu, Ms. Farhanah, Ms.Gurpreet, Ms. Jamie, Ms. Lau Mei Chien, Ms. Lily Lee, Ms. Nabilah, Mr. Ng Sweet Kin, Ms. Phang Ying Ning, Ms. Precilla, Ms. Rachel Tham, Ms. Rajalakshmi, Mr. Sivabalan, Ms. Tan Lee Siew Tutorial 3: Chapter 3 Stoichiometry and Solution Concentration 1. Balance the following equations: (a) (b) 2. V2O5(s) + CaS(s) CaO(s) + V2S5(s) GaBr3(aq) + Na2SO3(aq) Ga2(SO3)3(aq) + NaBr(aq) 316.0 g of aluminum sulfide, Al2S3 reacts with 493.0 g of water, H2O. Given the unbalanced equation as below: Al2S3(s) + H2O(l) → Al(OH)3(s) + H2S(g) (a) Find the excess reactant. (Ans: H2O) (b) Find the mole of the excess reactant that remains after the reaction. (Ans: 14.742 mole) [Sep 2014] 3. Consider the reaction below: 2Al(s) + 3I2(s) 2AlI3(s) (a) Determine the limiting reagent and the theoretical yield of the product if 1.20 moles of aluminium and 2.40 moles of iodine are used. (Ans: 489.218 g) (b) Calculate the percentage yield of the product if 450 g of AlI3 is obtained. (Ans: 91.98%) 4. A salt solution is produced when 2.9 g of sodium chloride, NaCl dissolved in 200 ml of water. Calculate the molality (m) of the NaCl solution...
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...NAME: AKINWANDE OLUFISAYO PARNTNER: COURTNEY DATE: JULY 8TH 2014. ALDOL CONDENSATION TO MAKE VANILIDENEACCETONE. DATA: REACTION: TABLE 1: DATA FROM EXPERIMENT | Vanillin | Acetone | Vanillindeneacetone | Chemical formula | C8H803 | C3H60 | C11H1203 | Molecular weight | 152.25 g/mol | 58.08 g/mol | 192.21g/mol | Density (g/cm3) | 1.06 | 0.788 | | Amount used | | | | Total moles | | | | Theoretical yield | | | | Percentage yield | | | | TABLE 2: DATA FROM EXPERIMENT: REAGENTS | Sodium Hydroxide | Hydrochloric Acid | Chemical formula | NaOH | HCl | Molecular weight | 39.997 g/mol | 36.46 | Denisty | 2.13 | 1.18 | Amount used | 3mL | 7mL | Total moles | 0.i598 | 0.227 | TABLE 3 : IR SPECTRUM Peaks (cm-1) | Functional group | 3699.8 | OH group | 3267.6 | Alkene | 1634.79 | Aromatic | CALCULATIONS: Total moles of Vanillin = 0.5g/152.15 = 0.0033 moles of vanillin. Total moles of acetone = (4mL * 0.788)/ 158.08 = 0.0199 moles of Acetone. Theoretical yields: Vanillin = 0.5g * 1mole * 1mole * 192.21 = 0.632g 152.15 1mole 1mole Acetone = 4ml * 0.788 * 1mole * 1mole * 192.21 = 3.832g 1mole 158.08 1mole 1mole Therefore, vanillin is the limiting...
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...Question 1 Which of the following is NOT a strong electrolyte? | | LiOH | | | CaCl2 | | | MgCO3 | | | NaC2H3O2 | | | Li2SO4 | 1 points Question 2 Which of the following compounds is soluble in water? | | CaS | | | MgCO3 | | | PbCl2 | | | BaSO4 | | | None of these compounds is soluble in water. | 1 points Question 3 Which of the following compounds is insoluble in water? | | Hg2I2 | | | MgSO4 | | | (NH4)2CO3 | | | BaS | | | All of these compounds are soluble in water. | 1 points Question 4 Give the net ionic equation for the reaction (if any) that occurs when aqueous solutions of Na2CO3 and HCl are mixed. | | 2 H+(aq) + CO32-(aq) H2CO3(s) | | | 2 Na+(aq) + CO32-(aq) + 2 H+(aq) + 2 Cl-(aq) H2CO3(s) + 2 NaCl(aq) | | | 2 H+(aq) + CO32-(aq) H2O(l) + CO2(g) | | | 2 Na+(aq) + CO32-(aq) + 2 H+(aq) + 2 Cl-(aq) H2CO3(s) + 2 Na+(aq) + 2 Cl-(aq) | | | No reaction occurs. | 1 points Question 5 Write balanced complete ionic and net ionic equations for the following reactions: AgNO3(aq) + NaCl(aq) --> AgCl(s) + NaNO3(aq) | | Ag+(aq) + NO3-(aq) + NaCl(aq) --> AgCl(s) + NaNO3(aq)Ag+(aq) + Cl-(aq) --> AgCl(s) | | | Ag+(aq) + NO3-(aq) + Na+(aq) + Cl-(aq) --> AgCl(s) + Na+(aq) + NO3-(aq)Ag+(aq) + Cl-(aq) + NO3-(aq) + Na+(aq)--> AgCl(s) | | | Ag+(aq) + NO3-(aq) + Na+(aq) + Cl-(aq) --> AgCl(s) + Na+(aq) + NO3-(aq)Ag+(aq) + Cl-(aq) --> AgCl(s) | | |...
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...oil mole ratio (1:6 to 1:24). The synthesis of methyl esters were achieved by an autoclave nitrogen pressurized reactor equipped with a magnetic stirrer and a thermocouple.42 A maximum yield (97%) of methyl ester was obtained at a temperature of 180 °C, 1:15 molar ratio of methanol and oil for a reaction period of 2 hours. The 3 wt% of catalyst amount and 350-360 min-1 agitation speed were fixed respectively to obtain good yields. 2.13. Esterification of free fatty acids in crude palm oil The production of biodiesel from the crude palm oil by the conventional method, using the homogeneous base catalyst contains large amounts of free fatty acid and it also results in the soap formation and thereby reducing the yield of biodiesel. To overcome these problems the free fatty acids need to be esterified to their esters by using an acid catalyst prior to alkaline catalysed transesterification. The sulfated metal oxide was found to be the best catalyst for this purpose due to its high acidic strength. The sulfated tin oxide solid acid catalysts were doped with aluminium and used in the transesterification reaction of free fatty acids present in the crude palm oil.43 A number of aluminium doped sulfated tin oxide catalyts were synthesised by using different aluminium presursors/starting materials. From the results, it is observed that the different aluminium precursors gave different acitivities of catalysts. The esterification reaction of free fatty acids with methanol using these catalysts...
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...Experiment 34A: Hypochlorite Oxidation of Methyl Ketones by the Haloform Reaction: Benzoic Acid Objective: To practice the Haloform reaction as synthetic rout to form benzoic acid To understand the mechanis that provide chorine from NaOH To obtain the melting point and FTIR spectrum of benzoic acid Experimental Procedure: The procedure was followed as described in Mayo, pages 405 -406, with the modifications given on Blackboard. Additional modifications to the procedure included the following: * The filtered product was left on the Hirsch funnel for 1 5 min * The amount of Na2SO3 was increased from 15 to35 mg * The amount of Acetophenone was increased from 15 to35 mg * The amount of Na2SO3 was increased from 90 μL, from 60 μL. * The amount of Sodium hypoclorite was increased to 3.2 mg Reaction scheme Data and Results: Physical properties Compound | Formula | MW | Amount | mmol | Mp 0C | Bp 0C | d | nD | Acetophenone | C₆H₅COCH₃ | 120.16 | 90 μL. | 77 | 20.7 | 2.2.6 | 1.03 | 1.5372 | Aquous NaOCl | NaOCl | 74.442 | 3.2mL | | 18 | 101 | 1.11 | | Sodium sulfite | Na2SO3 | 120.6 | 35mg | | | 33.4 | | | Benzoic acid | C6H5COOH | 122.12 | 94mg | 77 | 121.0 | 249 | | | Chloroform | CHCl3 | 119.38 | 92mg | | | | | | Water | H2O | 18.015 | 1.5mL | | 32 | 100 | 1.00 | | Observations: * Acetophenone and NaOCl were clear liquids * Sodium Sulfite was a whote powder * A yellow greasy liquid was found at the...
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...Surname Centre Number Candidate Signature Other Names Candidate Number Leave blank General Certificate of Education January 2006 Advanced Subsidiary Examination CHEMISTRY Unit 3(a) Introduction to Organic Chemistry Wednesday 11 January 2006 9.00 am to 10.00 am CHM3/W For this paper you must have G a calculator. For Examiner’s Use Number Mark Number Mark Time allowed: 1 hour Instructions G Use blue or black ink or ball-point pen. G Fill in the boxes at the top of this page. G Answer all questions. G Answer questions in Section A and Section B in the spaces provided. G All working must be shown. G Do all rough work in this book. Cross through any work you do not want marked. G The Periodic Table/Data Sheet is provided on pages 3 and 4. Detach this perforated sheet at the start of the examination. Information G The maximum mark for this paper is 60. G The marks for questions are shown in brackets. G This paper carries 25 per cent of the total marks for AS. For 1 Advanced Level this paper carries 12 2 per cent of the total marks. G You are expected to use a calculator where appropriate. G The following data may be required. Gas constant R = 8.31 J K–1 mol–1 G Your answers to the question in Section B should be written in continuous prose, where appropriate. G You will be assessed on your ability to use an appropriate form and style of writing, to organise relevant information clearly and coherently, and to use specialist vocabulary, where appropriate. Advice G You are advised...
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