Experiment To Investigate the Effect On the Rate of Reaction Caused By Changes In Temperature.
Experiment to investigate the effect on the rate of reaction caused by changes in temperature. Plan The Aim of this experiment is to investigate the effect on the rate of reaction caused by changes in temperature. Safety Safety in this case includes: * The use of a heatproof mat * Sensible setup of equipment so that the desk is clear and everything is stable * Setting the bunsen to a safety flame while it is not in use * Wearing goggles while using hydrochloric acid and sodium thiosulphate * Wearing an apron to protect clothes Fair Test To make any experiment a fair test, I must make sure that I wash and dry the apparatus after every test so that the substances do not get contaminated. Also, because the solutions are both clear it would help to use different sizes of measuring cylinder and beaker so that the two liquids can be distinguished Equipment Theory The rate of reaction is the amount of a substance that takes part in a chemical reaction in a given time. The main thing that can change the rate of reactions is a catalyst because they provide an easier path to overcoming the activation energy. Concentration also affects reaction rate. A higher concentration increases the amount of particles that can collide. If reacting substances are heated, the rate of the reaction usually rises because the particles that make up the substance already have more
To investigate the effect of the concentration of nitric acid on the rate of reaction between the nitric acid and magnesium granules.
FACTORS AFFECTING RATES OF REACTION AIM: To investigate the effect of the concentration of nitric acid on the rate of reaction between the nitric acid and magnesium granules BACKGROUND KNOWLEDGE: The equation for this reaction is: Word: Magnesium + Nitric acid Magnesium Nitrate + Hydrogen Gas Balanced Equation: The products of the reaction between nitric acid and magnesium are magnesium nitrate, water and hydrogen gas. In my main investigation, I will measure the rate of reaction by calculating the volume of hydrogen gas produced, using a gas syringe, over a certain time period. I will then plot a graph of gas produced against time for all of the different concentrations of nitric acid. Having plotted gas produced against time for each concentration, I will then take a tangent of the line produced by each concentration graph and calculate the rate of reaction for each concentration. The rate of reaction will be calculated as follows: Rate of reaction = volume of gas produced/time (cm³/second) Having done that, I will plot a graph of rate of the reaction for each concentration against concentration, and then state what type of relationship there is between the concentration of acid and the rate of reaction. I will then be able to conclude and state from my results what type of relationship my results show as explained on the following page. I will then analyse
Sodium Thiosulphate + Hydrochloric Acid Coursework
Sodium Thiosulphate + Hydrochloric Acid Coursework Plan Aim I must produce a piece of coursework investigating the rates of reaction when Sodium Thiosulphate + Hydrochloric Acid are mixed. The reaction that will be used is: Na S O + 2CHl 2Na Cl + S + SO + H O Sodium + Hydrochloric Sodium + Sulphur + Sulphur + Water Thioslphte Acid Chloride Dioxide Variables Other variables, which may affect the outcome of this experiment, if not kept constant, are as follows: o Temperature of liquids. I believe that the hotter the temperature, the faster the rate of reaction. This is because when a substance is heated up, each particle has more energy, resulting in more collisions between the free moving particles in a liquid, causing more particles to react, therefore increasing the overall rate of reaction. The second effect this has is that the particles collide with more force, increasing the chance of the particles reacting. I will keep this variable constant so that it does not affect the results by avoiding heating the sodium thiosulphate in any way, and so it will stay at room temperature. o Human Error/People. This experiment relays on people and their eye sight, because to determine how long
Limiting Factors & the Rate of Photosynthesis.
Limiting Factors & the Rate of Photosynthesis James Irwin Introduction Photosynthesis can be defined as the production of simple sugars from carbon dioxide and water causing the release of sugar and oxygen. For photosynthesis to take place a plant requires carbon dioxide, water, light, a suitable temperature, chlorophyll and availability of nutrients. The raw materials of photosynthesis are carbon dioxide and water. Carbon Dioxide is the only form in which a plant can take in carbon, however, in this case using an aquatic plant, in may obtain it from hydrogen carbonate ions in the water. The limiting factors of photosynthesis are: * Light Intensity If you put a plant in total darkness, it cannot photosynthesize at all. As the amount of light is increased, the rate of photosynthesis increases until the chloroplast is working at full capacity. At this level of light intensity, adding more light makes not difference to the rate of photosynthesis. In fact, it may reduce it, because very bright light can bleach chlorophyll and make the leaf much less efficient. This graph resembles that as the increase in light intensity (which can be measured in lux) increases, the rate of photosynthesis, until another factor such as carbon dioxide or temperature, limits it. * Concentration of Carbon Dioxide Carbon dioxide is needed to make sugars in the leaf. Carbon dioxide is present
Investigate the effect of concentration on the reaction between Thiosulphate ions (S2O32-) and H+ ions.
(1) Skill area P: PLANNING Problem: Investigate the effect of concentration on the reaction between Thiosulphate ions (S2O32-) and H+ ions. Introduction: When sodium Thiosulphate solution reacts with acid, a precipitate of sulphur forms. The time taken for a certain amount of sulphur to form can be used to indicate the rate of reaction. In this experiment the effect of concentration of sodium thiosulphate on the rate of this reaction is investigated. Prediction: I predict that as the concentration of sodium thiosulphate, (Na2S2O3) in MoLdm-3 increases it will take a shorter time for the sulphur precipitate to form. Thus: * The higher the concentration, the faster the rate of reaction. This is also vice-versa, * The lower the concentration the slower the rate of reaction. Background Information: Collision theory: If solutions of reacting particles are made more concentrated there are more particles per unit volume. Collisions between reacting particles are therefore more likely to occur. Also, When the temperature is increased the particles will have more energy and thus move faster. Therefore they will collide more often and with more energy. Particles with more energy are more likely to overcome the activation energy barrier to reaction and thus react successfully. If solutions of reacting particles are made more concentrated there are
" To KILL ,or not to KILL: that is the question"
Marcin Stenka Sem. IV Gr."A" Opinion essay " To KILL ,or not to KILL: that is the question" Around the world, animals are used to test products ranging from hand cream to new cancer drugs. Almost every medical treatment you use has been tested on animals. The question is: should animals be used in medical experiments? I strongly believe that, even though people cause harm to animals ,these experiments are useful and not once saved life of human being. In the first place, without tests progress in medicine would not be possible and many of well known cosmetics would not exist. Antibiotics invented to cure great diseases such as: polio, measles, mumps ,rubella were also tested ,but not on human. For example ,animals were also used to develop anesthetics to prevent human pain and suffering during surgery. Moreover, HIV drugs and insulin rely on animal tests ,because other testing methods aren't advanced enough. Furthermore, human living standard goes up. Can one imagine better life without soap ,toothpaste, perfumes or make-up? Without mentioned people appearance and scent would not much differ from animals. For instance , currently cosmetics are used almost everywhere at home, at work etc. Many of us are not able to live without medicines. One can function as normal having incurable disease. In addition to this, operations on animals helped to develop organ transplant. It
"A comparison of soils (e.g. garden/ school / park / woodland) linked to controlling environmental factors".
Kirby Kruger I.B Higher Biology Group lab test "A comparison of soils (e.g. garden/ school / park / woodland) linked to controlling environmental factors". Planning (a) Introduction and background information Soil is an abiotic factor when considered as a natural surrounding. Different soil types affects individual species of plants and animals. A good example of how soil type affects plant life is to compare two different ecosystems with different soil compositions. The desert plains in central Australia consist of mostly sandy soil. The sand does not retain water well and is very dry and arid, but the plants have adapted so that their life cycles are completed in the 30 days that follow a good rainfall. Only some succulent plants which retain water very well manage to survive throughout the whole year. A comparison may be a peat bog; cold, waterlogged and deficient in nutrients, mosses and plants which obtain minerals through "alternative" methods (carnivorism) thrive here. Soil supports the basis of the Earth's ecosystems, and the agriculture and economy of the world. The three main types of soil include: * Sandy soils, which are light, heat up quickly and retain water poorly. Particles are relatively large with relatively big airspaces. A sample with more than 90% sand particles is just called "sand". * Clay soils and silty soils, which tend to be cold,
"An experiment to investigate how a factor affects the rate of photosynthesis"
BIOLOGY COURSEWORK YEAR 11 BY ABHINAV SARASWAT TITLE: "AN EXPERIMENT TO INVESTIGATE HOW A FACTOR AFFECTS THE RATE OF PHOTOSYNTHESIS" PLANNING EXPERIMENTAL PROCEDURES Photosynthesis is a process in which plants make their own food. Photosynthesis uses carbon dioxide, water light and chlorophyll to produce glucose and oxygen. They do this by taking in the carbon dioxide (CO2) from the air around it. The plant also needs water (H2O) and light (either from the sun or from other sources such as a light bulb). Most of the plants food is made in the palisade cell, which is in the leaf of a plant. Leaves are perfect for photosynthesis because they are flat and thin providing a large surface area for the absorption of light and gases. Photosynthesis happens in the leaf because there are a large number of chloroplasts there, each chloroplast contains the green pigment chlorophyll that gives the leaf its green colour and also captures light energy for use in the process of photosynthesis. In photosynthesis the light absorbed by chlorophyll powers the reaction that converts water and carbon dioxide into glucose and oxygen. Both animals and plants for respiration use oxygen produced by photosynthesis. The word equation for photosynthesis is: Carbon dioxide + Water Glucose + Oxygen The balanced chemical equation for photosynthesis is: 6CO2 + 6H2O
"An investigation to find out the optimum temperature for the activity of Lipase".
"AN INVESTIGATION TO FIND OUT THE OPTIMUM TEMPERATURE FOR THE ACTIVITY OF LIPASE" * AIM To investigate the effect of temperature has on enzyme activity and the hypothesis that there is an optimum temperature for the activity of the enzyme lipase. * INTRODUCTION Enzymes are catalysts made up are protein molecules, usually with a globular structure. They accelerate chemical reactions in organisms that would otherwise occur to slow. (Green, Stout, Taylor, 1991) Lipase is a digestive pancreatic enzyme which works to hydrolyses fats into glycerol and fatty acids. (Simpkins, Williams, 1987) These products will react with the Sodium Carbonate (put into the mixture to raise the pH) and in effect lower the pH level towards a more acidic content. This pH change can be observed by using the indicator Phenolphthalein, which changes from a pink colour to colourless at a pH below 8.3. * HYPOTHESIS Lipase is an enzyme found in the human body and from knowledge of human enzymes I expect the optimum temperature to be around 40°C. I also expect that at low or high temperatures the rate of reaction will be slowest. * METHOD MATERIALS USED: Electric Kettle, 100ml Beaker, 10 Boiling tubes, 2 Boiling tube racks, Milk, Sodium Carbonate, Phenolphthalein, Spirit Thermometer, 5% Lipase. PROCEDURE: STEP 1: We mixed 5cm³ of milk with 7cm³ of Sodium Carbonate and added 6 drops of
"Are rechargeable batteries more economical than alkaline batteries?"
IB Extended Essay 07-05-2003 Candidate Name: Willy Gunawan Candidate Number: D0612-027 School: Wesley College, Melbourne School Number: 0612 Subject: Chemistry "Are rechargeable batteries more economical than alkaline batteries?" Words: 3711 Acknowledgements: 07/04/2003 I acknowledge that the work of others has been appropriately referenced and that all unacknowledged work is genuinely mine. Along with this I want to thanks all the support given by my family, and Ms. Karen Hamilton which has been very patient in guiding me and was a tremendous mental support and me during this hectic time of doing the assignment itself. Thank you, for making it possible for me to finish the project. As English is my second language, a lot of effort and time has been put into ensuring that my language is properly used, and make sense. Yet it is inevitable that I made linguistic mistakes along the way. I would like to use this opportunity, to apologise if that is the case. Willy Gunawan Contents: Title Page..............................................................................................1 Acknowledgements..................................................................................2 Table of Contents....................................................................................3 .
