|
|
|
|
|
Rates of reactions between HCL and magnesium ribbon
|
|
|
Rates of reactions between HCL and magnesium ribbon Aim I plan to investigate the effect of concentration of acid, in the reaction between dilute hydrochloric acid and magnesium ribbon. The rate of a chemical reaction is a measure of how fast the reaction takes place. It is important to know that a rapid reaction is completed in a short period of time. Some reactions are very fast, for example; the formation of silver chloride precipitates when silver nitrate and hydrochloric acid solutions are mixed. In this investigation I will test different concentrations of acid reacting with magnesium. /Plan To investigate what effect concentration of sodium thiosulphate has on the rate of reaction. The volume of HCL needs to be kept at 10cm3 constantly each time. Start with 60cm3 of sodium thiosulphate. Last reaction will have only 10cm3 of sodium thiosulphate. Reactions will be completed when the x disappears, for the timing to stop. Three reactions will be made for each test; this is done to gain the different averages. Introduction I will be conducting an experiment on the rate of reaction for my GCSE coursework. I will be doing this coursework for a period of two weeks. We will be reacting sodium thiosulphate with hydrochloric acid. I will be investigating the effects had on rate of reaction. When sodium thiosulphate and hydrochloric are mixed, a yellow precept of sulphur is produced. The solution becomes increasingly difficult to see through as more and more sulphur is formed. Prediction My prediction is that as the concentration of the hydrochloric acid increases, the time taken for the magnesium to disappear decreases. I predict that when the concentration of the hydrochloric acid doubles, the rate of the reaction doubles. Background Knowledge: Rate is a measure of how fast or slow something is. For example, Silver Chloride precipitating (this is a very fast reaction) and Concrete setting (it may take a couple of days for concrete to harden). Rate is a measure of the change that happens in a single unit of time. Any suitable unit of time can be used - a second, a minute, an hour and even a day. To find the rate of reaction, you should measure: The amount of reactant used up per unit of time or the amount of a product produced per unit of time. We are going to do an experiment on the rate of reaction. We are using acid and magnesium strips to test the rate of reaction. Rates of reaction can be varied by a number of factors: ? The concentration of the acid in which the magnesium is placed, ? The temperature of the acid and ? The size of the surface area of the magnesium strip. Why rate changes with concentration If the concentration of the acid is increased, the reaction goes faster. 1 2 - Acid Particle - Water Molecule - Magnesium Atoms 1. In dilute acid, there are not so many acid particles. This means there is not much chance of an acid particle hitting a magnesium atom. 2. Here the acid is more concentrated - there are more acid particles in it. There is now more chance of a successful collision occurring. The more successful collisions there are the faster the reaction. This idea also explains why the reaction between magnesium and hydrochloric acid slows down as time goes on: 1 2 - Acid Particle - Water Molecule - Magnesium Atoms 1. At the start, there are plenty of magnesium atoms and acid particles. But they get used up during successful collisions. 2. After a time, there are fewer magnesium atoms, and the acid is less concentrated. So the reaction slows down. Why rate changes with the temperature At low temperatures particles of reacting substances do not have much energy. However, when the substances are heated, the particles take in energy. This causes them to move faster and collide more often. The collisions have more energy, so more of them are successful. Therefore the rate of reaction increases. Why rate increases with surface area The reaction between the magnesium and acid is much faster when the metal is powdered: 1 2 - Acid Particle - Water Molecule - Magnesium Atoms 1.
|
|
|
|
Still Can't Find What Your Looking For? Then Try a Essay Search!
|
