Investigating The Reaction Between

Calcium Carbonate + Hydrochloric Acid Calcium Carbonate + Water + + Carbon Dioxide

CaCO3(s) + 2HC(aq) CaCl(aq) + H2O(l) + CO2(g)

The reaction between Hydrochloric Acid and Calcium Carbonate is being investigated because it produces a gas called Carbon Dioxide. This gas can be collected and is therefore a reliable result to base the investigation on.

Variable Why will this variable affect the rate of gas production?

Volume of HCl The more HCl used in this experiment would increase the rate of gas production, as there is more solution for the calcium carbonate chips to react with.

Concentration of HCl There are more reactant particles, therefore a greater chance of them colliding. So there are more collisions, increasing the rate.

Temperature of HCl The reactant particles are moving quicker and more particles have activation energy. There are more collisions, which increases the rate.

Time gas collected for If there is more time than more particles are colliding, increasing the rate of gas collected.

Mass of calcium A grater mass of calcium means there are more particles to collide, increasing the rate.

Surface Area of Calcium Carbonate If the surface area is increased, there are more exposed to the other reactant. The reactant particles collide more often so the rate increases.

The dependant variable of this experiment is the volume of gas produced in a certain time.

And the independent variable is the mass of calcium of calcium carbonate.

Prediction

I predict that if the mass of calcium carbonate chips is increased then the reaction time will increase. Looking at my graph from the preliminary results I predict that if the mass of calcium carbonate is doubled, then the volume of gas production will double. In the preliminary experiment the gas production for 1g was 34cm3, in the second with a 2g mass the volume was 95cm3, this is approximately 2.5 times the amount in the first experiment. This is a good guide to see how much the mass affects the rate of gas production.

The theory for my prediction is that if the mass of calcium carbonate is increased, than there is a greater chance of reactant particles colliding, which will increase the rate of gas production.

Apparatus

o Stop-watch Ð'- to time the reaction.

o Conical Flask Ð'- to put the calcium carbonate Ð''chips' and hydrochloric acid in to do the reaction.

o Bung Ð'- to prevent any gas escaping, except through the glass tube.

o Calcium Carbonate Ð''Chips' Ð'- a reactant for the reaction.

o Hydrochloric Acid Ð'- a reactant for the reaction.

o Measuring Cylinder Ð'- to collect the gas in, to give a result.

o Trough Ð'- to fill with water, to collect gas in the tube.

o Clamp Ð'- to hold the measuring cylinder in place.

o Stand Ð'- to hold the clamp on.

o Glass Tube Ð'- to connect the conical flask to the measuring cylinder, for gas to be carried along it

The other independent variables will be controlled to ensure a fair test. Masses will be kept the same each time as they will be weighed out properly, the volumes of solutions will be measured accurately using measuring cylinders and the temperature will be kept constant as it will all be carried out at room temperature.

The method for this experiment is better than the preliminary study as more detail has been included and a prediction. The safety of this experiment will be to wear safety glasses, due to 2M hydrochloric acid is being used.

Results