Investigate how the concentration of hydrochloric acid effects the rate at which it reacts with calcium carbonate :: GCSE Chemistry Coursework Investigation

Investigate how the concentration of hydrochloric acid effects the rate at which it reacts with calcium carbonate Investigation Plan Aim === Investigate how increasing the concentration of the solution hydrochloric acid effects and alters the rate at which it reacts with marble chip, calcium carbonate. Rate of reaction is affected by six main factors * Temperature * Surface area of a solid * Concentration of a solution * Pressure of a gas * By using catalysts * Using biological catalysts called Enzymes As outlined above the rate of a reaction increases when temperature increases, the concentration of dissolved reactants increases, the pressure of gases increases, solid reactants are in smaller pieces and of greater surface area and also if a catalyst is used. For this experiment I have been asked to pay particular attention to the factor CONCENTRATION, and the ways in which it affects the rate at which a reaction takes place. We can measure the rate of reaction by measuring the time at which the products of the reaction are produced or the reactants used up and there are a few different ways of doing this such as: By measuring gas volume Here the marble chips and dilute hydrochloric acid are put in a conical flask. This is connected to a gas syringe, which collects and measures the volume of gas formed. At regular time intervals a measurement is then taken of the volume of gas collected. Another way to measure the volume of gas produced is to displace water from a measuring cylinder as per diagram below. We can also measure the rate of reaction by measuring mass loss here when a gas is lost the mass decreases, which can be measured by placing the flask on a balance. The last way is to note how long it takes for a precipitate to form such as in the chemical reaction "the thiosulphate reaction". I conducted a preliminary experiment and from this determined that the most reliable and accurate way to measure the release of carbon dioxide gas would be by using a measuring cylinder to see the displacement of water and therefore determining how much carbon dioxide has been produced. Hypothesis I predict that as time increases so will the amount of carbon dioxide produced however throughout the experiment the rate of reaction will slow because as time increases there will be less and less un-reacted particles present to take part in fruitful collisions and result in carbon dioxide water and calcium chloride being formed, this means that the time between fruitful collisions will increase because a particle will take longer to find another un-reacted particle with enough activation energy to collide and react with. I hypothesise that as the concentration of the hydrochloric acid