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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

    The Effect of Concentration on the Rate of Reaction between Magnesium [Mg] and Hydrochloric acid [Hcl]

    4 star(s)

    - Collision theory was introduces by Max Trautz and William Lewis in 1916. Chemists believe that the theory explains how the various factors affect reaction rates. It is believed that molecules are only able to react if they bump into each other. When molecules are colliding with each other it can lead to other theory's affecting this such as concentration, temperature and catalysts. The theory states that when molecules are colliding with one another atoms can break and new bonds form creating new molecules. There are molecules in gases and liquids which are always in constant motion colliding in millions.

    • Word count: 4377
  2. Marked by a teacher

    Investigation of the rate of reaction between Magnesium and Hydrochloric acid

    4 star(s)

    Advantages: 'Rate of reaction graphs' are easy to plot using the results from this method. It is the most accurate method because the mass balance is very accurate. Disadvantages: The gas is released straight into the room and if the flask is not covered by the cotton Wool properly, drops might escape from the flask which lowers the total mass of the solution unnecessarily. Name: Gas Syringe Description: This method involves the use of a gas syringe to measure the volume of gas given off. The more gas given off during a time interval, the faster the reaction.

    • Word count: 3932
  3. Marked by a teacher

    Rate of Reaction Chemistry Coursework

    4 star(s)

    This variable in my experiment must stay the same, if I want to achieve reliable results. It has to stay constant otherwise it would be unfair and the results wouldn't be reliable. I will keep it constant by using the same amounts of reactants for each experiment. I will have to decide on the amount of hydrochloric acid I use and the amount of magnesium I will use and keep them the same for every experiment that I do. If I do this I would have this variable controlled. Surface Area- Any reaction in a solid has to take place at the surface at the solid.

    • Word count: 4087
  4. Marked by a teacher

    Marble Chips and Hydrochloric Acid.

    4 star(s)

    To be sure I can rely on my results I will repeat he experiment twice or three times if necessary, because there is chance of inaccurate results for many reasons. I learnt from the trial experiments that it is quite hard to start a stopwatch, pour acid and stick a bung into a boiling tube all at the same time, so I will get someone to assist me while doing so. If the experiment goes on for a ridiculous time, I will cut it off.

    • Word count: 4637
  5. Marked by a teacher

    In this investigation we are going to measure the rate of reaction of marble and HCl when the concentration or surface area of marble is changed.

    3 star(s)

    We tested using different concentrations of HCl and different surface areas of marble so we could have a set of results to help us compare with our main results, to help us determine the accuracy of the results. Apparatus ? Small and medium marble chips ? 1M and 2M HCl ? Water trough ? Conical flask- where the reaction takes place ? Delivery tube and bung ? Two measuring cylinders- one to measure out HCl and the other to collect CO2 ?

    • Word count: 3941
  6. Marked by a teacher

    For my experiment I am finding out the effects on the reaction rate when magnesium is put into different concentrations of hydrochloric acid.

    3 star(s)

    Therefore changes in the temperature could impact the reliability of the results. The concentration of hydrochloric acid is a factor that, I intend on changing by adding varying amounts of water to dilute the acid. The concentration, if changed, will also cause a doubt in the reliability of the results. This is due to there being less or more molecules of hydrochloric acid than when the concentration is not altered. In my experiment it is a factor that I wish to change and monitor the effects in doing so (independent variable).

    • Word count: 5878
  7. Marked by a teacher

    Rates of reaction of agar with different HCL concentrations

    3 star(s)

    Reactions that involve collisions between more than two species are going to be extremely uncommon. It is clear to understand that if you have a situation involving two species they can only react together if they come into contact with each other. Firstly they have to collide then they may react. Why "may react"? It isn't enough for the two species to collide - they have to collide the right way around, and they have to collide with enough energy for bonds to break in the reactants. (The probability of all this happening if your reaction needed a collision involving more than 2 particles is remote.

    • Word count: 3109
  8. Marked by a teacher

    What affects the rate of a reaction? The reaction I will be investigating is the reaction of marble chip (Calcium carbonate) with hydrochloric acid.

    3 star(s)

    In my experiment I chose to use concentration as my independent variable. The reason why I didn't choose temperature was because; I didn't have the facilities to control the temperature precise enough that it would be an accurate test. The reason why I didn't choose catalyst was because; I wasn't able to get my hands on a catalyst that would be suitable and it would cost too much for me to buy a catalyst. So this left me with surface area and concentration, the reason why I didn't choose surface area was because; with the resources available that would be

    • Word count: 3532
  9. Marked by a teacher

    How dose temperature affect the rate of reaction between magnesium and hydrochloric acid.

    3 star(s)

    This is to suture the acid and make sure that magnesium is always covered in acid. This will so make sure that the magnesium is in contact with unreacted acid this will make the reaction faster and I will be able to do more repiates. The second problem was that the magnesium had the top layer oxidised. This means some magnesium has already reacted with the oxygen in the air. I needed to depose of this because otherwise it could have effected the speed of the reaction, I am sur that the magnesium oxide reacts differently with hydrochloric acid.

    • Word count: 3900
  10. Marked by a teacher

    The Effect of Concentration on the Rate of Reaction between Hydrochloric Acid and Calcium Carbonate (marble) Chips.

    3 star(s)

    Chemical reactions can also occur at diffenet speeds depending on their factors and their enviroment. In this reaction the factor that will be investigated is the different concentrations of hydrochloric acid on small marble chips, and how fast its rate of reaction is in producing a certain amount of carbon dioxide. From research gathered and previosuly conducted experiments, it has been established that the higher the amount of concentration there is in each solution the faster the rate of production. I have decided there will be five concentrations tested, 100ml3, 75ml3, 50ml3 25ml3 and 0ml3; each test will be repeated twice to create an average for each experiment, to guarnatee all the results are correct and are similar to one another to prevent anomalies.

    • Word count: 4294
  11. Marked by a teacher

    In this project I am going to investigate rates of reaction of an indigestion tablet when added to hydrochloric acid. The variable I am going to use will be the temperature of the acid.

    3 star(s)

    and have more chance of colliding with each other. Also, there is a greater chance of effective collisions. However, unlike concentration, this is not proportional. As the temperature begins to increase, the rate increases slowly, but as it gets higher the rate increases faster, creating a curved graph. * Catalysts Catalysts are substances which increase the rates of chemical reactions but are not used up or altered in any way altered themselves. They provide an alternative method of collision requiring less energy.

    • Word count: 4782
  12. Marked by a teacher

    Chemistry Coursework - How the concentration effects the rate of reaction between sodium thiosulphate and hydrochloric acid.

    As the concentration is higher this means that there are mare sodium thiosulphate molecules to react with HCl molecules. As the HCl will be kept as a constant there will always be the same amount of molecules but as the sodium thiosulphate is being watered down this means that there will be less molecules for more successful collisions. What happens is the molecules in the two solutions mixed will be "free" as a figure of speech until they collide with another molecule that it can react with and the end result should be a yellow precipitation to be formed.

    • Word count: 3859
  13. Peer reviewed

    Rates of Reaction

    5 star(s)

    The rate of reaction is the speed of the reaction. It is how quickly a reaction takes place. There are three ways of measuring the rate of reaction. These are 1) Precipitation - this is when a product of the reaction is a precipitate which clouds the solution. Observe a marker through the solution and measure how long it takes for it to disappear. 2) Change in mass (usually a gas given off) - any reaction that produces a gas can be carried out on a mass balance and as the gas is released the mass disappearing is easily measured.

    • Word count: 5142
  14. Measuring the reaction rate of sodium thiosulphate in hydrochloric acid

    For this investigation we were permitted to investigate the effect of either concentration or temperature as we did not have the necessary equipment to study the other factors. 2.2 Collision Theory Collision theory is a theory which qualitatively explains how chemical reactions occur and why reaction rates differ for different reactions. It was first proposed by a German chemist called Max Trautz in 1916. It states that for a reaction to occur the reactant particles must collide. However, only a certain fraction of the total collisions cause chemical change; these are called successful collisions.

    • Word count: 3491

    Again, if the surface areas of the membranes are very different between potato samples, diffusion will occur faster in cells where there is a greater surface area, as it means there are a more places to cross the membrane. The shape of the samples; the shape of the samples should be the same as the volume of two shapes can be the same, but one may have a greater surface area than the other. If some samples are different shapes and so have different surface areas to other, there will be a greater chance for osmosis to occur, as the surface area affects the rate of osmosis.

    • Word count: 5168
  16. Magnesium Oxide

    So this means that the lengths would need to go up in 5 (5cm, 10cm, 15cm, 20cm and 25cm). Since 5, 10, 15, 20 and 25 all add up to 75 this would be the only logical method. Using a range this big also allows me to be able to make a comparison between the lengths because the results would end up being very different. Possible Formulas for magnesium oxide Formula Mass of Magnesium (g) Mass of Oxygen (g) Mass of Magnesium Oxide (g) Point to Plot MgO 24 16 40 (24, 40) Mg2O 48 16 64 (48, 64)

    • Word count: 3008
  17. Investigating the rate of a reaction

    As my independent variable I have chosen the concentration of hydrochloric acid. I will also need a dependant variable, which is the variable I will be measuring. I have chosen the amount of carbon dioxide formed as the dependant variable. To complete the investigation fairly and accurately I will need to keep the amount of calcium carbonate used, the amount of hydrochloric acid and the temperature used the same as these would be my control variables. In my investigation I had decided to investigate how the concentration of an acid affects the rate of the reaction.

    • Word count: 5659
  18. An investigation into the effect of concentration on the rate of chemicl reaction between sodium thiosulphate and hydrochloric acid.

    How rate of reaction is measured 1) Measure how long it takes for a reaction to be completed. E.g.: the rate of reaction of magnesium with hydrochloric acid can be measured by timing how long it takes a piece of magnesium ribbon to dissolve in hydrochloric acid. The shorter the time, the faster the reaction 2) Measure the amount of reaction product produced in a given. E.g. the rate of reaction in a marble chips(calcium carbonate) with hydrochloric acid can be measured by recording the volume of CO2 gas produced at a regular time intervals The steeper the graph, the faster the reaction 3)

    • Word count: 3007
  19. The purpose of this coursework is to investigate the factors which affect the rate at which zinc reacts with sulphuric acid to form zinc salt and hydrogen.

    However, occasionally they do hit each other so hard that reaction can occur and the rate of reaction depends on how often these mega bumps happen. Evidently the more mega bumps in a given time the faster the reaction. The most powerful collision is a fast, head to head collision as opposed to a slow glancing collision. It is not enough for molecules to collide. Bonds between the atoms must be broken before new molecules can be made. This process requires energy.

    • Word count: 4078
  20. Investigating Rates of Reactions

    Measuring the mass-loss as time goes on; * Measuring the mass-loss per unit time is a slightly less appealing method to use in my opinion. This is because as the magnesium reacts with the HCl, obviously the volume of the magnesium decreases and so the mass will also decrease as mass is determined by volume (mass = density x volume). However considering the mass of the magnesium is not very high; it will take very sensitive scales to measure the very slight changes in the mass as the reaction proceeds.

    • Word count: 6412
  21. Free essay

    Close Your Eyes

    The room I'd always felt safest in was no longer mine. Soon it would belong to someone else and they would be lying in their bed listening to the wind blowing the tree's branches up against my window. I walked out the front door and avoiding eye contact, walked past mum, not even acknowledging her existence. I still hadn't forgiven her and I never will. She didn't have to accept this job. She could have stayed where she was, she was perfectly happy. It's not like she's even getting paid extra.

    • Word count: 36078
  22. Rates of Reaction- Hydrolysis of Urea by Urease

    However a chemical bond is not formed between the enzyme's active site and the substrate, so after the reaction has occurred the product is released and the enzyme remains unchanged. Another theory is 'induced fit' where the enzyme and substrate interact with each other and the enzyme changes the shape of the active site to fit the substrate. There are factors which affect the rate of the enzyme reaction, such as temperature, pH, and amount of the substrate and enzyme concentration.

    • Word count: 5145
  23. Rate of Reaction

    The faster the reaction, the shorter the time taken for the effervescence to stop. I will study the effect of changing the concentration of hydrochloric acid on the rate of reaction. In this project I am going to measure the concentration of different amounts of hydrochloric acid. My aim for this coursework is to find a pattern between the concentrations of the acid. A method I can use is to measure the amount of gas produced. This is where I can use a gas syringe and time how much gas is produced every 15 seconds.

    • Word count: 5434
  24. Chemistry Cwk Rates of reaction: Investigating One Factor Which Affects How Fast Calcium Carbonate Reacts With Nitric Acid

    Potential factors that could be investigated with the provided equipment and time would be temperature, concentration and surface area. An increase of temperature affects the rate of a reaction because it provides the particles with more energy. The energy this theory refers to is the kinetic energy of the particles and, therefore, the speed at which they move. The temperature the reactants are subjected to will not vary the quantity of particles so the area under the line on the graph of energy distribution will remain the same, but there will be a larger area with activation energy. This is because a certain number of particles which, before, did not have enough energy to react would now, with the increase of temperature, move past the activation energy mark.

    • Word count: 4683
  25. Rates of reaction between Magnesium and HCl.

    Such problems cannot be fully controlled with the equipment available but steps can be taken to avoid them. This is why the same person reads off the gas produced, measured the length of magnesium, fill the burette with water, and also the same person should time. To ensure that this experiment will be a fair test, I will make sure that: > I will use the same length of magnesium ribbon > Keep the volume used the same > Conduct the investigation in similar temperatures (RTP)

    • Word count: 3778

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