Reaction Rate Between Calcium Carbonate And Hydrochloric

Acid Essay, Research Paper

Calcium carbonate and hydrochloric acid react together. Plan an investigation to examine the factors that effect the reaction rate between them.

I am trying to find out what affects the reaction rate of calcium carbonate and hydrochloric acid. Things that affect the reaction rate are the temperatures of the hydrochloric acid, the amount of hydrochloric acid, the concentration of the hydrochloric acid, surface area of the calcium carbonate, amount of calcium carbonate and the form of calcium carbonate. (It is available in three forms powder, small stones or large stones)

I have decided to investigate into how the concentration of the hydrochloric acid affects the reaction rate between them.

I think that the less concentrated the hydrochloric acid is the longer it will take for it to react with the calcium carbonate. I think this because the higher the concentration of the hydrochloric acid is, the higher the chance of the bonds breaking because the stronger the hydrochloric acid is the more energy the molecules have so they travel with more force which means the bonds break. If the molecules do not have much energy they will just bounce of the bonds harmlessly. The energy is needed to break the bonds and get the reaction started. Rates of reaction can be changed not only by catalysts but also by changes in temperature and by changes in concentrations. Raising the temperature increases the rate by increasing the kinetic energy of the molecules of the reactants, thereby increasing the number of collisions per second and the likelihood of transition states being achieved. Increasing the concentration can also increase the reaction rate by increasing the rate of molecular collisions.

Concentration ofConcentration is higher so

The acid lowtheirs more chance of

The particles colliding.

I am going to change the concentration of the hydrochloric acid to 5 different concentrations 100%, 75%, 50%, 25% and 0%.

I am going to do this by taking 5cm3 of hydrochloric acid away and replacing it with water.

100% = 20cm3 hydrochloric acid

75% = 15cm3 hydrochloric acid and 5cm3 water

50% = 10cm3 hydrochloric acid and 10cm3 water

25% = 5cm3 hydrochloric acid and 15cm3 water

0% = 20cm3 water

I am going to time how long it takes for each different concentrated acid to react with the calcium carbonate with a stopwatch.

I am going to try and make my investigation as fair as I possibly can by repeating the process as many times as I can and get an average by adding them all together and dividing by the number of results I get. Also I will use the same amount of calcium carbonate which is 0.25grams and the same amount of liquid which is 20cm3. Each time I start my experiment I will make sure the beaker is clean and dry.

Hopefully it will be safe because I will wear safety spectacles and take as much care as possible while walking with any beaker, substance etc. in my hands so the calcium carbonate or hydrochloric acid will not come into contact with anything else than each other.

I will need 50cm3 of hydrochloric acid,50cm3 of water, 1.25g of calcium carbonate (this is based on collecting results once) beaker, measuring cylinder, stop watch and weighing scales.

I am going to measure 20cm3 hydrochloric acid, add it to 0.25g of calcium carbonate then time the reaction rate.

Then I will measure 15cm3 of hydrochloric acid and 5cm3 of water add the calcium carbonate and time the reaction rate. Then I will measure 10cm3 of hydrochloric acid and 10cm3 of water add the calcium carbonate and time the reaction rate. Then I will measure 5cm3 of hydrochloric acid and 15cm3 of water add the calcium carbonate and time the reaction rate. Then I will measure 20cm3 of water add the calcium carbonate and time the reaction rate. I will repeat this process as many times as I can.

ConclusionResult 1Result 2Average

100%10.958.989.97

75%18.1916.2617.23

50%25.1527.9826.56

25%62.4464.1963.32

0%128.98134.45131.76

During the practical I came across some difficulty?s, when I was adding the calcium carbonate its was sticking to the bottom because it was damp to resolve this problem if I were to do it again I would do it on a dry day.

Also when I added the calcium carbonate some fell over the side so it was not a very accurate 0.25g. And the paper that I weighed the 0.25g on was also slightly damp so some calcium carbonate got stuck to it so that varied my reading a little.

Due to the time of our lesson I had to complete the practical over two lessons so the room temperature may have been different so that may have changed the reaction rate a little.

Also this meant I had two use two different bottles of hydrochloric acid so my first set of results slightly differed to my second set.

Overall the experiment was not very accurate due to the listed problems above.

If I were to do the experiment again I would still investigate how does concentration effect the reaction rate but I would concentrate enough hydrochloric acid to cover each set of results.

Also I would try and do it on the same day so the conditions were approximately the same. Theirs is nothing I could do to make sure the amount of calcium carbonate is exactly the same each time.