Investigating the relationship between the concentration and the rate of Carbon dioxide production w

... goes on. The main problem is that I was unable to measure all of the oxygen being released from the marble chips as some of the oxygen is given off as soon as the marble chips meets the hydrochloric acid and some off it isn? measured. However my results were very much how I expected them to turn out to be. Limitations in preliminary work: As expected there were a few limitations to my preliminary work. The first limitation was that the surface area of the marble chips exposed to the hydrochloric acid was uncontrollable. As a result of this my results may vary because if the surface area increases so does the amount of oxygen released from the marble chips. Another limitation was that the top pan balance that I used to measure the mass of the marble chips wasn? very accurate. This was due to the fact that the balance didn? measure the mass to any decimal places it only rounded off to a whole number and as a result of the factor my results weren? entirely accurate. The final limitation that I contended with was that I was unable to use the same hydrochloric acid once the calcium carbonate chips had been placed in. this was largely due to the fact that some of the hydrochloric acid had been decomposed therefore I would need to use a clean beaker with a new solution for the other marble chips. Plan: In this investigation I plan to change the mass of the marble chips and keep the concentration of the hydrochloric acid the same. Also to witness the relationship between the mass and the rate of oxygen produced. Variables: A variable is something, which can be measured or controlled. A dependant variable is a variable you must keep identically the same. I must only test one variable at a time. The independent variable is the one I alter or test. These are my variables. ?he size and mass of the marble chips used. ?he surface area of the marble chips exposed to the hydrochloric acid. ?he ph of the hydrochloric acid. ?he concentration of the hydrochloric acid. ?he temperature. ?he time limit used to measure the amount of oxygen released. ?he volume of hydrochloric acid. These are important factors, which will affect the outcome of my results so if my results are to be as accurate as possible then I must be able to ...