Science Coursework Rates Of Reaction

I will then measure how long it takes for a chemical reaction to take place.The time might vary depending on the concentration of Sodium thiosulphate.This is basically how hard and how often particles collide with each other.

sodium thiosulphate hydrochloric acid sodium chloride water sulphur dioxide sulphur Na2S2O3(aq) 2HCl(aq) 2Na Cl(aq) H2O(l) SO2(aq) S(s) Prediction I predict that the higher the temperature, the more quickly reaction will occur.

This is because with heat, the particles of sodium thiosulphate and hydrochloric acid have more energy. It works like this for all substances, not just those two.

In a high concentration of acid it can take just a few seconds for magnesium to furiously bubble and finally completely dissolve with no trace except for hydrogen gas.

Equation of magnesium and hydrochloric acid: 2 HCl Mg [IMAGE]Mg2 H2 Measuring rates of reaction In this investigation there are two experiments that can be used to test rates of reaction.

· Surface area raises the amount of collisions because if you split a reactant up into smaller pieces then you will be expanding its surface area.

This means that the particles which are around the reactant will have more surface area to work on, and this means that there will be greater amount of successful collisions per second.If there are greater amount particles then there will be greater number collisions taking place and so the rate of reaction increases as well as the temperature.The collision theory explains us that if a chemical reaction is to take place, the particles in a substance have to collide into each other with enough energy to break bonds and hence to form new bonds.Chemical reactions require collisions, and if particles are moving around more quickly they are obviously more likely to collide. If the people are moving quickly it is more likely that they will bump into each other then if they are moving slowly.It is in this way that particles of solutions react. I will measure the rate of reaction by mixing the different quantities of Sodium thiosulphate (50 - 10cm³) with a fixed quantity (5cm³) of hydrochloric acid in a Conical flask and placing the flask on top of a white sheet of paper with a cross clearly marked on it. In this piece of science coursework I will be experimenting how the rate of reaction between Sodium thiosulphate and hydrochloric acid is affected by the concentration of Sodium thiosulphate.Using a gas syringe As more gas is produced the plunger inside the syringe moves out of the syringe so the gas can be measured by marks on the syringes length.I would have to measure the amount of hydrogen produced in regular intervals which would change for each concentration.I will do this by timing how long it takes for the cross to disappear.I will be measuring the quantity of sodium thiosulphate and hydrochloric acid I use, by using a ‘pipette’ and a measuring cylinder, which will allow me to precisely conduct my measurements.