This extended experimental investigation (EEI) investigated the effect in which concentration had on the rate of reaction. The purpose of this experiment is to test different concentrations of hydrochloric acid with sodium thiosulfate and to see how long it would take until the cross underneath the flask is no longer visible through the milky white solution.
Collision theory
A collision is when two or more object run into each other. But collision theory is, that only some particle collisions make changes (or are fruitful). Fruitful or effective collisions require enough energy to break pre existing bonds and form new ones. In order to have enough energy the particles they need to have the right orientation and enough force. …show more content…
There a five ways to speed up reaction rates. The first is to get the particles moving faster, this is done by heating up the particles, giving them more kinetic energy. The second is to increase the surface area, increasing the likelihood in which the particles will have contact with each other because it now has a greater surface area, this can be achieved by breaking down solids. The third is concentration, concentration speeds up the reaction rates as having more particles in the same area increases the likelihood in which they will collide. The fourth is adding a catalyst, a catalyst reduces the amount of activation energy required to break the pre existing bonds and form new ones. The final is to lower the volume of a reaction vessel or mixture, this mean there is less room for the particles to move and the more likely collision will occur.
Aim: To understand how concentration effects rates of reaction.
Hypothesis: The results of this experiment will show that there will increase reaction rate the more concentrated hydrochloric acid is, because there are a greater number of reacting particles henceforth creating more fruitful …show more content…
This will have an effect on the resulting time because people’s perception can differ between individuals, therefore them seeing in the cross disappear before others. Also the first trail we did, we put 40ml of 0.2 molar of sodium thiosulfate and 5 drops of hydrochloric acid, this resulting in the experiment taking over 25 minutes without making the cross disappear. Furthermore the second time the experiment was performed the reaction was relatively fast, which means percentage wise it would better if the reaction was slower because the accuracy would be better. This experiment only tested 3 concentrations of hydrochloric acid, not only more concentrations give us a more accurate results but it could give us more of an expediential growth in time the less concentrated the hydrochloric acid. If this experiment was to be done again it would could be better by test more concentrations, getting the same person to decide when the cross has disappeared and limit the amount of hydrochloric acid that is used so that the reaction will take