Hydrogen Gas Collection Lab CE (6/6) A sample of solid magnesium ribbon, measuring approximately 2.5cm and weighing 0.037 g +/- 3% was allowed to react with an aqueous solution of hydrochloric acid
Conclusion and Evaluation: A sample of solid magnesium ribbon, measuring approximately 2.5cm and weighing 0.037 g +/- 3% was allowed to react with an aqueous solution of hydrochloric acid, with a concentration of 6 mol dm-3 in a 1000cm3 graduated cylinder. The sample of magnesium was wrapped in a cage constructed of copper wire, and mounted on a holed rubber stopper, which was inserted into the end of a gas measuring tube, with 14.90 cm3 +/- 0.3% of 6 mol dm-3 HCl(aq) already in the tube with the rest of the gas measuring tube being filled with tap water. The gas measuring tube was then inverted into the 1000cm3 graduated cylinder, in which there was 790 cm3 +/- 0.6% of tap water, and was allowed to react with the 6 mol dm-3 hydrochloric acid once it had descended down to where the magnesium strip lay since hydrochloric acid is denser than water (As told by teacher). This, in a vigorous reaction, produced a gas that ascended to the top of the gas measuring tube, and it can be said that it is mostly comprised of hydrogen gas, as per the following, balanced equation: Mg(s) + 2HCl(aq) --> MgCl2(aq) + H2(g) (Michigan State University, n.d.) Considering the main reactants are solid magnesium ribbon, and 6 mol dm-3 hydrochloric acid, the gas produced is hydrogen gas. The hydrochloric acid did not react with the copper wire that was holding the magnesium ribbon in place because
ÉTUDE SUR L'EFFET DU COURANT COMME FACTEUR D'INFLUENCE DANS LA QUANTITÉ DE PRODUITS EN CUIVRE DURANT SA PURIFICATION AVEC UNE PILE ÉLECTROLYTIQUE par Félicia Latour Travail présenté à M. Marc Pilon dans le cadre du cours de chimie 12e SCH 4UI-01 Collège catholique Franco-Ouest Le mardi 5 janvier 2009 ) BUT La question préliminaire de ce laboratoire a demandée : " Quelles sont les facteurs qui affectent la quantité de produits formés lors de l'électrolyse? ". À partir de ceci, j'ai pu concevoir un laboratoire ayant comme but de déterminer la relation entre la quantité de produits durant la purification du cuivre avec une pile électrolytique, soit la masse de cuivre transférée, et le courant qui . Il s'agit donc de trouver une relation soit proportionnelle ou inversement proportionnelle entre le courant du circuit et la quantité de produits. 2) HYPOTHÈSE ET THÉORIE Une pile électrolytique s'agit d'un système composé d'électrodes, d'un électrolyte et d'un circuit extérieur portant une source de tension. Elle va consommer de l'énergie au lieu de la fournir car elle utilise l'énergie du courant fournit pour convertir de l'énergie électrique en énergie chimique. Cette pile est l'inverse de la pile galvanique et elle a une réaction globale qui est non spontanée. Une particularité de cette pile est l'inversement des signes +/- ; la
Options B: Medicines and Drugs B.1.1: List the effects of drugs and medicines. A drug or medicine is a chemical that alters incoming sensory sensations, mood or emotions, or physiological state. Painkillers, hallucinogens and alcohols are examples of drugs and medicines that alter incoming sensory sensations. Prozac and alcohol alter mood or emotions Steroids, cigarettes and heart medicines alter physiological state, including consciousness, activity level or coordination. Drugs such as antiseptics, antibiotics and antivirals are infection fighters; hormones and vitamins affect body chemistry or metabolism; stimulants, depressants, analgesics and anesthetics affect the central nervous system and the brain. It is also important to understand that the human body has great natural healing processes; some drugs just increase the rate of natural healing. Also, there could be a placebo effect, it is when a pharmacologically inert substance that make seems to help because the person taking the substance was told that it would work. Placebo effect is examined by giving sugar pills to one group of tests patients, and real drugs to another group (when they are not aware of which they receive). B.1.2: Outline the stages involved in research, development and testing of new pharmaceutical products. This takes a very long time and costs a fortune, and is often controlled by the
YEAR 11 CHEMISTRY ONE WORLD ESSAY Are you consuming too much fuel? April 2007 Contents Page Introduction Page 3 My family fuel consumption Page 3 Local / Global: Where do I stand? Page 4 Impacts Page 6 Potential Alternatives Page 7 Limitations of study Page 8 Conclusion Page 9 Bibliography Page 9 Introduction During the last few years, the world has developed in both technological and scientifical aspects. Currently, we are dependant on fuel for almost every action we take. We use electricity to light our homes, natural gas to heat our food, and petrol to travel in our cars. Although each individual consumes a different amount of fuel, all amounts of consumption have great impacts on the world. Electricity consumption has been estimated to "increase by 71% from 2003 to 2030"1, which, no doubt, will have a drastic effect on the world. For this reason, in this essay, I will focus on the consumption of electricity as a fuel. To begin with, I will calculate and compare my family's fuel with the average consumption of a Portuguese family to discover where my family stands. I will then look at the societal, ethical and moral impacts and effects, as well as investigate potential alternatives to decrease my family's fuel consumption. While
Using Solubility Rules to Indentify Unknown Solutions Chemistry IA In this experiment, known aqueous solutions are combined to investigate whether a precipitate id formed. These results are then used to deduce the identity of two unknown solutions and thus the identity of the precipitate. Table of Contents Focus Question: 2 Hypothesis: 2 Theory: 2 Variables: 3 Control Used for Comparison: 3 Apparatus and Material: 3 Safety Aspects: 4 Protocol and Protocol Diagram: 4 Procedure 4 Modifications to Original Design: 5 Data Collection and Processing: 5 Photograph of Lap Setup: 5 Qualitative Observations and Raw Data: 6 Data Processing 7 Overview: 7 Sample Calculations: 7 Presentation: 8 Conclusion and Evaluation 9 Conclusion and Justification: 9 Limitations to Experimental Design: 10 Suggestions for Improvements: 10 Appendix -1- Table of Ions and Polyatomic Ions 12 Bibliography 14 EXPERIMENTAL DESIGN Focus Question: Which pairs of 6 ionic combination solutions form precipitates and therefore aid in determining the two unknown solutions? Hypothesis: The two unknown solutions will be determined from chemical reaction observations obtained from pair ionic combinations resulting in precipitate formation. Theory: A solution is a homogeneous mixture that contains a solute dissolved in a solvent. A solution is made by dissolving the required amount of
Thermodynamics: Enthalpy of Neutralization/ Calorimetry Introduction The First Law of Thermodynamics states that energy can be neither created nor destroyed. This means that energy, instead of 'disappearing', is either transformed, transferred, dispersed, or dissipated. When energy is lost by a system, it will be acquired by the surroundings. Heat can be described as the amount of energy needed to cause the temperature of a substance to rise and it is transferred from warmer areas to cooler ones. In order to be able to measure the change in heat or enthalpy of a reaction, a colorimeter can be used. The calorimeter was first introduced in the 18th century and can be used with any procedure that involves the flow heat between a system and it's surroundings (CACT). It is capable of measuring the heat created or exchanged after a reaction has occurred in a system with a constant pressure. A calorimeter can be used to find the specific heat of a substance or even the heat of neutralization between a base and an acid. A basic calorimeter is composed of two Styrofoam cups (to provide insulation and prevent heat from entering or exiting the system), a lid covered with aluminum, a thermometer, and a stirrer. Since the calorimeter will still release heat, the first step is to find the heat capacity of it which is the heat absorbed by the calorimeter. In order to find the heat
Bomb calorimetry. The goal of this experiment was to use temperature data over time from combustion reactions to calculate the heat released and then produce an experimental value for the heat of formation of naphthalene.
Experiment 1. BOMB CALORIMETRY Experiment Date: Jul 27, 2012 Formal Report: Aug 1, 2012 Student name: Suri Hoang (220080192) Abstract The goal of this experiment was to use temperature data over time from combustion reactions to calculate the heat released and then produce an experimental value for the heat of formation of naphthalene. After running a calibration trial of benzoic acid in the bomb calorimeter, the heat capacity of the calorimeter was 0.0699 kJ K-1. Using this value, the experimental enthalpies of combustion for naphthalene were -4982.66 ± 99.6532 kJ mol-1 which was a 3.44% error from the literature value of -5160 ± 20 kJ mol-1 (NIST Chemistry WebBook, 2008), and the enthalpy of formation was -86.8478 ± 1.736956kJ mol-1. Errors to account for in this experiment were due to the accuracy of weighing the substances, reading the thermometer, the measurement of water. Overall, this experiment was a success as each objective of the experiment was completed and the experimentally determined enthalpy of combustion of solid naphthalene was very close to its literature value. Introduction To find heats of combustion for certain reactions, it is feasible to use a bomb calorimeter. Due to heavy insulation, a calorimeter is adiabatic. Thus, the system is isolated from the environment. This way, combusting a chemical sample in the calorimeter
Biodiesel Investigation - How the concentration of Potassium Hydroxide solution would affect the yield of biodiesel when transesterified with a standard sample of vegetable oil .
1th May 2015 Biodiesel Experiment Introduction ‘Biodiesel is a clean burning renewable fuel made using natural vegetable oils and fats.1 Biodiesel is a revelation to chemists, engineers and environmentalists who are looking for more sustainable ways to make use of fuels. Since it is a natural and renewable fuel, it can be fitted in as a substitute for petroleum diesel, which is the substance conventionally used in automobile transport. Biodiesel is normally utilised as a replacement for petroleum diesel fuel or can be blended together with petroleum diesel fuel in any ratio. Biodiesel is a biodegradable substance with a lower toxicity in comparison to petroleum diesel fuel and is preferred as it is safer to handle since there is little human risk involved in its handling. The use of biodiesel as a petroleum substitute reduces the degree of exhaust emission. Biodiesel are notorious for their easy use in terms of how they can easily be pumped and stored in existing engines without having to make major industrial alterations to the engines themselves. They are usually blended together with petroleum fuels in order to create the optimal usage in engines. The output yield of biodiesel is I had never really heard of biodiesel until it was a topic covered in school. After finding out what biodiesel was, I looked into the IB chemistry syllabus to see what points it had on
Kinetics Review Questions . Define rate of reaction 2. What are the units of the rate of reaction? 3. Outline procedures by which you could obtain a value for the rate of reaction 4. Draw a graph that shows the concentration of products with time as a reaction goes to completion. Explain the shape of the graph. 5. Draw a graph that shows the concentration of reactants with time as a reaction goes to completion. Explain the shape of the graph. 6. Outline the main features of collision theory 7. Give two reasons why a collision would not result in a reaction 8. The reaction between nitrogen and oxygen in the atmosphere under normal conditions is extremely slow. Which statement best explains this? A. The concentration of oxygen is much lower than that of nitrogen B. The molar mass of nitrogen is less than that of oxygen C. The frequency of collisions between nitrogen and oxygen molecules is lower than that between nitrogen molecules themselves D. Very few nitrogen and oxygen molecules have sufficient energy to react 9. List 4 factors that affect reaction rates and explain why using the principles of collision theory. 0. Define activation energy 1. Sketch a Maxwell-Boltzmann Energy Distribution Curve for two different temperatures. 2. Does activation energy change with temperature? 3. How does the number of molecules with the required activation energy change
Chemistry Lab Report - Molecules in a drop of a liquid Research question - How many molecules are there in a liquid drop? Variables - Independent variable - The nature of the liquid drop. Dependent variable - Mass of liquid drop. Constants - * Concentration of the liquids * The volume of a drop * Temperature of the liquids Hypotheses and prediction - The heavier the liquid used i.e. a liquid with a high relative molar mass, the more the number of molecules per drop. I predict this as the RMM (relative molar mass) is the measure of the mass of molecules that make up a mole of a substance, and hence the higher the mass is, the more the number of molecules there have to be. Thus, the liquid would have more number of molecules per unit volume as compared to one with a lower RMM, keeping in mind the same concentration is taken. Apparatus - . Measuring scale, in grams (± 0.01 g) 2. Dropper 3. Beaker, 50 ml 4. Distilled water 5. Glycerine 6. Ethanol 7. Ethylene glycol 8. Tissue paper Methodology - . We collected the apparatus needed and measured the mass of the 50 ml beaker. We called it m1. 2. Using a dropper, we put 20 drops of water in the beaker. We measured the mass of the beaker + water, and called it m2. The mass of the 20 drops of water was found by subtracting m1 from m2. The answer was divided by 20 to find out the mass of one drop of water. 3. We