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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

    Rate of Reaction - Sodium Thiosulphate and Hydrochloric Acid

    3 star(s)

    close as reasonably possible, I will when doing this take into account surface tension and hence fill so the actual amount in the measuring cylinder is at 10ml not a little under as it may appear. I will then add (starting with 50ml descending in steps of 5ml to 20ml) sodium thiosulphate to the 50ml measuring cylinder. Following this I will add (starting with 0ml rising to 30ml in steps of five, in such a manner that the total volume of water combined with sodium thiosulphate Is always at 50ml)

    • Word count: 1516
  2. Marked by a teacher

    In my investigation I am going to look at how concentration affects the rate of reaction, and the reaction I am going to look at is Sodium Thiosulphate (Na2 S2 O3) and Hydrochloric Acid (HCl).

    3 star(s)

    When the "X" is obscured the reaction has went to the same point. Prediction I predict that the stronger concentration of sodium thiosulphate, the quicker the "X" will be obscured as there are more successful collisions occurring per second, which will mean a greater rate of reaction. The higher the concentration will mean more particles present in the same volume, which will lead to more collisions and therefore more successful collisions which increases the rate of reaction Low Concentration - Few Collisions High Concentration - More Collisions I predict that more water added to the solution of Sodium Thiosulphate and Hydrochloric Acid, the longer "X" will take to be obscured.

    • Word count: 1580
  3. Marked by a teacher

    I measured the effect of concentration on the rate of reaction. The reactants were Sodium thiosulphate and Hydrochloric acid.

    3 star(s)

    The chances of collision are higher when the concentration is higher. For many reactions that involve liquids or gases, the increase of concentration on the reactants will increase the rate at which the reaction takes place. The point at which the reaction starts is called the energy barrier. When this energy barrier is reached, the chemical bonds in the reactants can be broken, which allows them to proceed from reactants to products. The main outcome of this experiment found, is that the higher the concentration of sodium thiosulphate, the faster the rate of reaction becomes.

    • Word count: 1255
  4. Marked by a teacher

    Chemistry rate of reaction coursework

    3 star(s)

    To counter this a water-bath will be used as I can keep the temperature at a constant. So my aim is to change the concentration in the Sodium Thiosulphate by adding water and taking away Sodium Thiosulphate gradually. The reaction of the experiment will be as follows: Sodium Thiosulphate + Hydrochloric Acid Na2S2O3 (aq) + 2HCL (aq) For my preliminary investigation I used the variable concentration to give me an idea of the range of results and what to expect in my final investigation.

    • Word count: 1297
  5. Marked by a teacher

    Rates of Reaction

    3 star(s)

    I will be able to tell when the reaction is complete because the solution will turn opaque enough to obscure the cross underneath the flask from view. Controlled -The volume of hydrochloric acid will be kept the same throughout the experiment because if it is changed it may affect my results. Also the concentration of the hydrochloric acid will be kept the same. -The volume of sodium thiosulphate solution, I will change the concentration of the solution, but not the volume because this may affect my results.

    • Word count: 1315
  6. Marked by a teacher

    How does varying the concentration in a reaction affect the rate of reaction?

    3 star(s)

    a result of the experiment, I have decided to stop timing my actual experiment when the amount of hydrogen produced reaches 20 cm3. This is because I think it will give me enough time to stop the stopwatch quickly enough on the higher concentrations and will not take too long to produce the hydrogen for lower concentrations. Experiment 2 The aim of this experiment was to find out how the temperature of the reaction will change during my experiment. I put 3cm of magnesium into a conical flask which had 100cm3 of 2M of HCl.

    • Word count: 1835
  7. Marked by a teacher

    Chemistry: Practical Investigation

    3 star(s)

    Catalysts affect the rate of reaction by providing an alternate route with a lower activation energy requirement, meaning atoms / molecules don't need to be travelling so fast. I am able to keep the temperature at room temperature due to central heating, and there are no catalysts for this reaction. The surface area is harder to control as they do not all have precisely the same surface area, however I weighed 3 chips until they added up to 1.1g. Surface Area: 2 Temperature 2 Concentration 2 Preliminary Method Firstly I set up the apparatus as shown under the apparatus but

    • Word count: 1391
  8. Marked by a teacher

    rate of reaction

    3 star(s)

    We should also dispose the mixture of chemicals of down a well-flushed sink. Equipment * Hydrochloric acid * Sodium thiosulphate * A paper with a black cross drawn on it * A conical flask * 2 measuring cylinders * 1 stopwatch * A pair of goggles Collision Theory The collision theory explains how a higher amount of collisions in a system, cause more combinations of molecules to occur. Moreover, how this affects the reaction to go faster, and the rate of reaction to become higher. Only a small part of the overall collisions cause chemical change; these are called successful collisions.

    • Word count: 1572
  9. Marked by a teacher

    How the Concentration of Acid in a Solution affects the Rate of Reaction

    3 star(s)

    (Theory explained thoroughly in conclusion). Preliminary Test: Before conducting the experiment I had first to determine the ratio of Hydrochloric Acid and Sodium Thiosulphate that give the best range of results. We observed how long it took 5cm� of Hydrochloric Acid (in different concentrations) to react with 10cm� of Sodium Thiosulphate. This was very slow and it was still possible to see the "X". I repeated this 3 more times increasing the volume of Sodium Thiosulphate but keeping the volume of the Acid the same.

    • Word count: 1432
  10. Marked by a teacher

    Rates of reaction throughout the year

    3 star(s)

    Information on acid rain: Fossil fuels give off a small amount of Sulphur, S. Acid rain will also be a mix of sulphurous and sulphuric acid and a small amount of nitric acid. The statue is reacting with sulphuric and sulphurous acid. The sulphur is coming from fossil fuels. Equation of acid rain: S+02 S02 S02+H20 H2S03 My Prediction: I predict that in summer, it will corrode more because the temperature is higher. When the temperature is higher more reactions will occur because of the increase in collisions.

    • Word count: 1711
  11. Marked by a teacher

    Rates of Reaction

    3 star(s)

    Also the rate of reaction is halved each time, there for it will take double the time to react. Although the particles may hit each other, they need to have hit each other hard enough to reach activation energy. It is when they reach activation energy is when they react with each other. The rate of the reaction is when more successful collisions happen per second. The reason why the rate of reaction is faster when the solution is more concentrated is that the ions are closer together in a concentrated solution.

    • Word count: 1324
  12. Marked by a teacher

    Rates of Reaction

    3 star(s)

    This increases the number of collisions. Solids with a smaller particle size react more quickly than solids with a larger particle size: Temperature If the temperature is increased the reactant particles move more quickly. The particles collide more often and more of the collisions result in a reaction, so the rate of reaction increases. At a lower temperature, the number of collisions is lower because the particles are moving more slowly. In addition, when a collision occurs there is less chance of a reaction-taking place because the movement energy in the particles is less.

    • Word count: 1889
  13. Marked by a teacher

    Investigating the Effect of Concentration on the Rate of Reaction between Hydrochloric Acid and Sodium Thiosulphate

    3 star(s)

    - using just 5cm� of 0.1M sodium Thiosulphate for the weakest solution simply took too long as it was so weak, so I decided to alter the concentration for the main experiment. I will change the concentration from 0.1M to 0.15M, so it will not take so long. Method I will need to do five tests, all of different concentrations. The concentration table below will show how much water and Sodium Thiosulphate will be needed per solution: Solution No. Volume of Sodium Thiosulphate (cm�)

    • Word count: 1290
  14. Marked by a teacher

    Chemistry copper sulphate and zinc

    3 star(s)

    This is because heat can be lost quickly through the sides of a glass beaker, and by using a polythene cup; I hope to cut this heat loss down. I will use 25ml of copper sulphate solution and 0.8125 grams of zinc in each experiment. I manage to work this out using Avogadro's theory of moles. First, I had to work out how many moles there are in 25ml of copper sulphate at 0.5M. We need to convert the 'ml' units into 'dm' units.

    • Word count: 1220
  15. Free essay

    Chemistry Rate of Reaction Coursework for Calcium Carbonate and Hydrochloric Acid

    The gas syringe has marks along its length which allow the volume of collected gas to be measured. The increase in volume can be timed, and a graph of volume against time can be plotted. This shows the rate of the reaction. Equipment: a gas syringe, rubber bung, conical flask, stand, clamp, 25ml hydrochloric acid, 2g medium sized calcium carbonate pieces, and a stopwatch. Method; 1) The gas syringe should be set up horizontally by an attachment to the stand, by the clamp. The tubing should be positioned well on the rear end of the gas syringe. 2)

    • Word count: 1805
  16. Peer reviewed

    Study on food colourings

    5 star(s)

    as Caramel colouring which is used is cola products, which is found in caramelised sugar and Annatto which is made from the seed in a tropical tree and used to create a reddish orange dye for food. Also natural food colourings can be made from many plants other plants. Natural colourings tend to be a lot more healthy and not such a threat to your health as some artificial food colourings. Health risks of artificial food colourings Different food colourings have different effects.

    • Word count: 1523
  17. Peer reviewed

    Cookies experiment Aim: To find out what type of powder reacts more towards heat and therefore expanding inside a cookie mix. Prediction: Based on the research I maid I think that the powder with the least different type of carbohydrates and elements wi

    4 star(s)

    Measure each cookie's length in cm. 8. Bake for 20 minutes at 200�C. 9. Measure the length of each cookie. Materials: � Metal and glass containers � Cookie mix � Ruler � Oven � Tea spoon � 5 different powders (sugar, coffee, cereal crumbs, chocolate milk powder and cinnamon) � Mold to cut cookie mix Variables: * Independent: The type of powder added to the cookie mix * Dependent: Change in length of cookie after being baked * Controlled: Mass of cookie mix for each cookie, amount of powder added, heat of oven, surface on which it was cooked on, type of cookie mix (ingredients), shape of the cookie, ruler used to measure and time inside oven.

    • Word count: 1038
  18. Peer reviewed

    To find out and analyse what factors affect the rate of reaction between limestone and acid rain.

    4 star(s)

    * Pressure (of gas) However in my experiment I am only going to investigate one of these factors. I have decided that surface area isn't the best one to choose because I only have 3 different sized marble chips so I wouldn't get a very large range of results to plot onto my graphs. I have decided to use concentration as my factor to investigate as I believe it will give me a better range of results and more interesting graphs to plot. Preliminary Experiment For my preliminary experiment, I reacted some hydrochloric acid (with a concentration of 2 moles)

    • Word count: 1101
  19. Peer reviewed

    Measuring the Rate of Reactions between Magnesium and Sulphic Acid

    3 star(s)

    Thus was Magnesium selected as a happy median. Reactions occur because of collisions between atoms. The faster the atoms move or the more crowded they are, the more successful collision transpire; thus causing a faster reaction. Several factors affect the rate of reaction, these are: * Catalyst: A factor that is added to a reaction to affect the reactions speed. * Concentration: How dense or concentrated a solution is affects the reaction. The more concentrated, the quicker the rate of reaction because there are more successful collisions.

    • Word count: 1191
  20. Peer reviewed

    An Experiment to Find the Amount of Heat Energy Released When 1g of Candle Wax Burns

    3 star(s)

    � Also make sure we know the mass of the candle (and its holder) � Then we need to take note of the initial temperature of the water with the thermometer � Set up the equipment as shown in the Diagram � Light the candle � Keep observing the thermometer readings until a significant gain in temperature is noticed and then take note of the mass of the candle and its holder in order to find out the mass of wax burned (by subtracting its mass after the experiment, by its mass beforehand) Before we undertake the experiment there are some points we must consider.

    • Word count: 1138
  21. Investigating the Factors Affecting the Rate of Reaction for the Iodine Clock

    The rate of a reaction depends on the number of successful collisions in a given amount of time. Concentration will affect this as if there are more particles, there is more chance of particles colliding. Therefore the reaction will occur sooner. Temperature would also affect the reaction speed because increasing the temperature would increase the speed of the particles. This would mean that more reactions would occur. Increasing the temperature would also increase the energy each particle has which would increase the amount of successful collisions. Surface area would affect the reaction speed because larger surface area would increase the chance of a reaction.

    • Word count: 1239
  22. Aim: To investigate how the concentration of sodium thiosulphate affects the rate of reaction.

    Timing how long it takes for a small amount of solid reactant to disappear - mix the solid and liquid in the flask and start the timer. Stop it when you can no longer see any solid. 4. Timing how long it takes for a solution to turn cloudy - this is for the reactions that produce an insoluble solid. Mix the liquids in flask and start the timer. Stop it when you can no longer see the cross on the paper through the solution.

    • Word count: 1145
  23. In my investigation, I intend to find out what effect changing the concentration of sodium thiosulphate has on the rate of reaction between hydrochloric acid and sodium thiosulphate.

    Theory I predict that the rate of reaction will be directly proportional to the concentration of sodium thiosulphate solution. When the concentration is low, then there will be less chance of successful collisions between the hydrogen ions and the thiosulphate ions and so, will take longer to react. However, if the concentration of sodium thiosulphate is increased, there will be more chances for the hydrogen ions and thiosulphate ions to collide. Also, if the concentration of the sodium thiosulphate is increased, then the ions will have more energy than they would if a low concentration were used. This means that more ions are likely to have activation energy needed for the reaction to take place.

    • Word count: 1046
  24. Rate of Reaction Lab Report

    And the collision theory states that the increase in successful collisions would increase the rate of reaction. Procedure The Variables Independent Variable How was it changed? Concentration of Hydrochloric Acid -Teacher provided. -Put a certain amount of hydrochloric acid that is 2 moles per liter in a beaker and put the same volume of water to make one with 1 mole. For 0.5 moles you put three times the volume and for 0.25 moles you put seven times the volume.

    • Word count: 1784
  25. Science Research Task- Francium

    Figures obtained from: http://www.docbrown.info/page03/Alkali_Metals.htm My predicted boiling point for Francium is 27�c Figures obtained from: http://www.docbrown.info/page03/Alkali_Metals.htm My predicted boiling point for Francium is 667�c Alkali metals often react violently, especially with substances such as water, halogens or Group 6 elements. This is due to their lone electron occupying the outer shell which is weakly attracted to the nucleus; therefore it is easily lost to other compounds with a high a tendency to attract/accept electrons such as hydrogen. As you go down the group the attraction between the only electron and the nucleus weakens, the reactivity increases and the reaction gets more violent.

    • Word count: 1013

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