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GCSE: Patterns of Behaviour

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  • Marked by Teachers essays 45
  • Peer Reviewed essays 15
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  1. Marked by a teacher

    Rates of reaction between hydrochloric acid and magnesium

    3 star(s)

    Therefore more reactant particles will have enough energy to react. Consequently the number of successful collisions increases. Concentration When increasing the concentration of reactants, the rate of reaction rises. If there are more particles in the same space of volume, the rate of successful collisions increases. The rate of reaction will change as the reaction progresses. When the reactants are used up during the reaction, the concentration of reactants decreases. Meaning particles collide less frequently and the reaction rate decreases. Exothermic and Endothermic These are reactions that transfer energy to the surroundings. The energy is usually transferred as heat energy, causing the reaction mixture and its surroundings to become hotter.

    • Word count: 2649
  2. Marked by a teacher

    The effect of concentration on the rate of reaction of Magnesium with Sulphuric Acid.

    3 star(s)

    Activation energy is the minimum energy required before a reaction can occur. There are several factors that can increase or decrease the chance of a successful collision. The factors that affect the rate of the reaction are; * Temperature - when we increase the temperature, we give the particles energy, which makes the particles move faster. Therefore the particles collide more and they are more likely to have the correct activation energy. The greater the temperature, the faster the rate of a reaction. * Surface Area - when we increase the surface area of the reactants we increase the number of particles available for a successful collision.

    • Word count: 2191
  3. Marked by a teacher

    Reaction Rates Investigation

    3 star(s)

    3 strips, 1cm each and 1 strip at 3cm. Here is a diagram for the most suitable method to use the apparatus we considered. We chose this method because in my opinion it is quicker to set up leaving more time for our actual experiment as we had limited time to complete it. The other apparatus involved a Burette in a clamp stand which was in my opinion just as effective as the more simple method of an upturned measuring cylinder which was a simple process to set up.

    • Word count: 2984
  4. Marked by a teacher

    Rates of Reaction

    3 star(s)

    Apparatus/ Materials: * 20ml of 0.5M HCl * 20ml of 1M HCl * 20ml of 2M HCl * 20ml of 3M HCl * 20ml of 6M HCl * 10g of Calcium Carbonate Powder * 1 Gas syringe * 5 200ml beaker * 1 25ml measuring cylinder * 1 rubber band Method: 1. Measure five 2g CaCO3 powder separately in five different 200ml beakers. (recommended to weigh with a scale (g)) 2. Measure a 20ml of HCl (with a measuring cylinder and use a pipette for small modifications)

    • Word count: 2546
  5. Marked by a teacher

    Lab report rates of reaction

    3 star(s)

    0.5 mole. If this is obstructed then concentration will play its part in the rate of reaction. Note: We should try our best to keep factors that affect the rates of reaction constant. For example temperature and pressure and concentration. This is because if they are differed they would hugely impact our results as they serve as catalysts to the reaction. So we should make sure temperature is constant, The same sizes fo flasks and bongs are used (so pressure is constant) and lastly we should make sure the concentration of the acids are left at 0.5 moles.

    • Word count: 2182
  6. Marked by a teacher

    The effects of concentration on reaction rates

    3 star(s)

    area where there aren't hydrogen or chlorine atoms, so the collision rate is likely to be higher. Prediction: I predict that the higher the concentration of HCl, the faster the reaction will take place. As I said in the introduction, the atoms will find it easier to react (collide) with the magnesium, as there would be more atoms to react with it. I think that the graph I will draw from these results will show proportionalities between the concentrations of the acid, and the time taken to react. However, the table wont show proportionalities, because it won't take into account the different differences between each concentration.

    • Word count: 2300
  7. Marked by a teacher

    To monitor the rate of reaction we measure how a product changes with time, I am going to collect the gas given off when magnesium reacts with different concentrations of hydrochloric acid at a given time.

    I have chosen these times because I only need three results as I am going to measure the initial rate of reaction and not the average. I will repeat each experiment so that my results are reliable and reproducible. * Hypothesis I predict that as the temperature increases, the speed of the reaction will increase therefore the gas will be produced faster. I believe this because most chemical reactions happen faster when the temperature is higher. At higher temperatures molecules mover around faster, which makes it easier for them to react together.

    • Word count: 2493
  8. Free essay

    Rate Of Reacion

    One example is temperature. There is a quicker reaction as higher temperate create more energy, therefore creating more collisions to be able to have a reaction. For our experiment we needed to increase the number of successful collisions between the reacting particle molecules. Temperature would increase the collisions taking place, however, for our experiment we did not use temperature to test the rate of reaction as it makes it very difficult, because it makes it hard to get reliable results as temperature can change very quickly.

    • Word count: 2338
  9. Marked by a teacher

    The aim of this investigation is to investigate the rate of reaction of magnesium (mg) with Hydrochloric acid (HCl). After studying the availability of equipment I have chosen to investigate how the temperature can affect the rate of reaction.

    Usually, a rise of 10OC will double the rate of reaction. Chemical reactions take place by chance. Particles need to collide with enough velocity so that they react. As the temperature is increased the particles move faster since they have more energy. This means that they are colliding more often and more of the collisions have enough velocity to cause a reaction. Since there are more collisions the chemical reaction takes place faster. To help me gain better knowledge about the investigation I have found out some scientific information relating to the experiment of 'rates and reaction'.

    • Word count: 2103
  10. Peer reviewed

    My experiment will be conducted to find out at what concentration does sodium thiosulphate with hydrochloric acid have the most reaction and how the concentration generally affects the rate of reaction.

    4 star(s)

    Measure temperature of room 4) Put a bold 'X' beneath the THIO beaker then pour HCL and press 'GO' on the stopwatch. 5) Press 'STOP' when solution goes cloudy and 'x' disappears. 6) Record results 7) See if it takes longer for the dilute solution to react. 8) Spot trends. Initial Method Na2S2O3 (aq) + 2HCl (aq) SO 2 aq) + S(s) + H2O(l) + 2NaCl (aq) My prediction: when the concentration of sodium thiosulphate is increased, the time taken for the reaction to take place will also decrease because the water molecules would delay the collisions between sodium thiosulphate and hydrochloric acid.

    • Word count: 2005
  11. How higher or lower concentration and temperature affects rates of reactions

    Sodium thiosulphate is a crystalline compound, which is colorless. It is produced from the waste product out of the liquid sodium sulfide, in industrial level. It has the shape of a tetrahedral form and it is the result of the replacement of an oxygen atom by a sulphur atom. The collision theory is when a chemical reaction occurs once different amounts of particles hit each other (collide). The faster the particles are moving the higher energy they contain and therefore are more capable to react when they collide.

    • Word count: 2473
  12. Investigating the rate of reaction between sodium thiosulphate and hydrochloric acid.

    Also the variables that will be measuring is the amount of sodium thiosulphate that is poured into the beaker and also the amount of distilled water that is poured into the beaker because I want to know how this mixture will affect the rate of reaction and how fast the reaction will be. Concentration will have an effect on the rate of reaction as in the case of this experiment; if the concentration of sodium thiosulphate is high then there more collisions there will be between it and hydrochloric acid which I assume will make the reaction quicker.

    • Word count: 2204
  13. Free essay

    Investigating the Rate of Reaction - Sodium Thiosulphate and Hydrochloric Acid

    If we change the concentration of the Sodium Thiosulphate, the higher the concentration of sodium thiosulphate, the faster the rate of reaction will be. Therefore, the black cross will fade away from sight more quickly due to the solution in the beaker becoming a cloudy pale yellow. In whatever constant variable is used (temperature or concentration), I will keep the amount of Hydrochloric Acid, the amount of solution depending on which constant variable the same. Another prediction is as the concentration is doubled, the amount of time taken to form a chemical reaction will be halved or approximately halved.

    • Word count: 2591
  14. What Affects the Rate of Reaction Between Sodium Thiosulphate and Hydrochloric Acid?

    + 2HCl (aq) � 2NaCl (aq) + H2O (l) + SO2 (g) + S (s) Preliminary experiment My experiment is designed to see how quickly the solution turns cloudy (how quickly the reaction produces sulphur). To start with, we simply tested the experiment method we would be using in our main experiment. There were a few different possibilities on how to conduct the experiment. We could have altered the temperature, but this would have been extremely difficult as we had little control over this variable anyway. We decided that to gain effective results, we should increase the amount of thiosulphate, whilst decreasing the amount of water.

    • Word count: 2904
  15. Free essay

    How does Concentration affect the rate of reaction between Hydrochloric Acid and Calcium Carbonate

    We did not choose surface area as cutting the calcium carbonate tablets was difficult as the tablets often crumbled once cut. This left concentration as the best possible remaining independent variable. I predict that the higher concentration of acid, the higher the rate of reaction. I predict this as collision theory states that "Anything that increases the number of successful collisions per second will increase the rate of reaction". The higher concentration of hydrochloric acid will increase the amount of successful collisions per second as there will be more hydrochloric acid particles to collide with the calcium carbonate particles.

    • Word count: 2857
  16. Health Implications of eating Fat

    This part of my coursework will explain what is meant by Monounsaturated, Polyunsaturated and Saturated fats or oils. Monounsaturated Fat Monounsaturated fats or (Monounsaturated fatty acids) are fatty acids that only contain one double bond in the chain and the rest of the remaining carbon atoms in the chain are single bonded. Fatty acids are long chained molecules with a methyl group at one end and a carboxylic acid group at the other. The fluidity of the fatty acids increases with the increasing number of double bonds. Monounsaturated fats have a higher melting temperature than polyunsaturated fats but lower than saturated fats.

    • Word count: 2353
  17. Physical and Chemical Properties/Changes of several household chemicals

    B. Physical and Chemical Changes 1. Approximately 20ml vinegar was obtained in a 150 mL beaker. One scoop of baking soda was tossed into the vinegar. A burning splint was then quickly placed near the mouth of the beaker. Observations were recorded in the data section. 2. a.) Approximately 40 ml 3M HCl (concentrated hydrochloric acid) was obtained in a test tube. b.) A 2 cm sample of magnesium ribbon was placed into the test tube containing the hydrochloric acid. Observations were recorded in the data. 3. a.) A small scoop of sucrose was placed into each of 2 test tubes.

    • Word count: 2130
  18. Titrations. For my science coursework I have been asked to carry out an experiment to investigate the strengths of different sodium hydroxide solutions. By the end of my experiment I would like to find out which solution would be the best antacid to overc

    Sodium Hydroxide solutions A, B and C, Hydrochloric Acid, Phenolphthalein (Indicator), Water. Strategy: In order to make this experiment fair I will be using 4 different methods to measure the acid used to neutralise the antacid solution. I will be using test tubes, beakers, measuring cylinders and the burette/pipette. I will test the equipment to see which method produces the most accurate results. By the end of the experiment I will be able to identify which method is the best and therefore conclude which equipment formed the most precise outcomes. Method 1 (Test Tubes)

    • Word count: 2518
  19. Investigating which alcohol is most efficient at heating water

    Diagram of apparatus can containing water x x x x x=clamps Heat (from spirit burner) Controlled variables-fair test To make the investigation fair I will ensure that as many variables as I can remain the same: * Liquid used * Amount of liquid (400ml) * Can used * Length of wick penetrating the top of the spirit burner * Distance of can above flame * Starting temperature of water * Ensure there are no drafts from open windows to blow the flame However, there are also uncontrollable variables such as: room temperature and soot on the bottom of the can etc.

    • Word count: 2362
  20. CHEMISTRY:OBESE

    In countries like America obesity is becoming more and more common, recent studies show that 39.8 million american adults, this is over 57% of American adults are overweight and seeing as obesity is passed on through genes from one generation to another the future is not looking bright and is becoming an increasingly worrying prospect. Also even more frightening is that every year there are over 300,000 premature deaths from obesity. What is the cause of obesity? Some cases of obesity are because of underlying disorders but most issues are caused by day to day living, basically your general lifestyle.

    • Word count: 2361
  21. Rates of Reaction - HCl + Mg

    From the collision theory, I know that reactants will only react if the atoms collide with sufficient energy. By increasing the temperature, the energy levels of the atoms involved in the reaction will be raised. The atoms move faster if the temperature is increased because they gain kinetic energy. Because they move faster, more collisions will occur in a space of time. Also, more successful collisions will occur because they will collide with enough energy to react. Concentration: Increasing the concentration will also increase the frequency of collisions the two reactants have. This makes collisions between the important particles more likely.

    • Word count: 2789
  22. Investigating how Temperature affects Rate of Reaction

    My independent variable will be the time taken for the X to disappear and this is the one I will measure. There are many other variables that will affect the reaction and therefore I will have to keep these variables constant to ensure a fair test and therefore reliable results. Firstly I will have to make sure the volume of the flask is kept constant as if the volume increases, the solution will be shallower and so the X will disappear more slowly.

    • Word count: 2272
  23. investigate the effects of temperature on the reaction between sodium thiosulphate and hydrochloric acid.

    When there is a higher concentration of reactants there is more chance of collision as there are more reactants to collide with. In effect, making collision easier makes reactions faster whilst hindering collision will only slower rate of reactions. Sodium Thiosulphate + Hydrochloric acid --> Sodium chloride + water + sulphur dioxide + sulphur Na2 S2 O3 + 2HCl -->?2NaCl + H2O + SO2 + S The sulphur that is formed is a white, insoluble precipitate, which turns the solution cloudy.

    • Word count: 2296
  24. Free essay

    Magnesium Ribbon

    Concentration is amongst these four factors and it is the one to be proved in this experiment. The collision theory states about concentration that if the concentration of an acid is increased, i.e. made stronger then lots more particles will collide and more successful reactions will take place. To get matching results with the prediction this investigation will include the concept of fair testing which will be done so by repeating the same experiment three times and also by changing only one variable while keeping the rest constant.

    • Word count: 2121
  25. To plan an experiment to investigate the effect of concentration on the initial rate of reaction between Calcium Carbonate and Hydrochloric Acid.

    I will then attempt to link my results with the statement that: as we increase the concentration, the rate of reaction increases. To do this I will make an educated evaluation using both the theory I have learnt in the classroom as well as the practical work I have carried out for this experiment. I have decided to measure the amount of product made, as the apparatus available only works for collecting the product i.e. collecting gas (carbon dioxide) over water.

    • Word count: 2262

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