Investigate the effect of changing the concentration of hydrochloric
acid and the volume of carbon dioxide produced by a reaction between
hydrochloric acid and marble chips (calcium carbonate).
Chemistry Coursework
To investigate the effect of changing the concentration of
hydrochloric acid and the volume of carbon dioxide produced by a
reaction between hydrochloric acid and marble chips (calcium
carbonate)
Planning experimental procedures
Aim
In this coursework I will be investigating to see how the
concentration of acid affects the rate of reaction with marble chips.
Hypothesis
Part 1
I predict that the rate of reaction between the acid and the marble
chips (calcium carbonate) will increase as the acid concentration
increases. This is because in an acid solution with a greater
concentration there are more particles present in the same volume of
acid. This means that there are more particles to collide and react
with the calcium carbonate. However the rate of reaction should
decrease as the reaction proceeds because the hydrochloric acid
molecules have been reacted to form water and carbon dioxide meaning
that the concentration of the acid decreases as the reaction proceeds.
'This should make the graph of the reaction curved. The curve will
start off steep, and will then start to curve towards the X-axis. The
curve is where the reaction slowed down'.
Part 2
On another set of graphs, which show the volume of carbon dioxide
produced against 1/time, the volume of carbon dioxide produced should
not be inversely proportional to time. This would be shown on the
graph with a curve that starts of steep close to the Y-Axis, and as
time progresses would curve away from the Y-Axis and towards the
X-Axis.
Part 3
'The increase in concentration of the acid and the initial reaction
rate should be directly proportional.' This means that should the
concentration of the acid be doubled then the time taken to produce
the same volume of carbon dioxide should be approximately halved.
'This is because there are twice as many molecules in a given volume
of acid. This means that the number of successful collisions is
doubled'.
My hypothesis is based upon the collision theory. The collision theory
states that 'the particles of the reacting substances must collide
with each other and a fixed amount of activation energy (Ea) (the
minimum energy required before a reaction can take place) must be
reached if the reaction is to happen. If a collision between particles
can produce enough energy a reaction will happen'. However not all
collisions will be successful (result in a reaction).
The equation for the reaction is:
Hydrochloric acid + calcium carbonate à Calcium chloride + water +
carbon dioxide
2HCl (aq) + CaCO3 (s) à CaCl2 (aq) + 2H2O (l) + 2CO2(g)
· Rinse out mixture in flask and leave water running to get rid of the
From the experimental data, the [H+] decreases as the concentration of the HCl in each solution decreases. Since acids dissociate in water, the dilution of the acid’s concentration (Macid) will determine the number of free hydrogen ions in the solution, being that they are equal to each other when the -log is used. By changing the concentration of the HCl, the acid strength decreases, as shown in the change in pH, due to the presence of H+ ions as they break away from the original molecules of the acid. These free ions are in the form of hydronium ions, which shows in the decrease of the H+ in the table above.
and therefore there is more area for the acid to react with it, and so
Investigating How the Concentration of Hydrochloric Acid Affects the Rate of Reaction with Calcium Carbonate
The reason I believe this is that chemical reactions occur when particles of the reacting substances collide. Increasing the number of the particles increases the number of collisions per second and this increases the reaction rate. In the reaction between hydrochloric acid and calcium carbonate you can increase the number of particles in two ways. The first of these is to increase the surface area of the calcium carbonate.
Investigating the Effects of Dilution on the Rate of Reaction Between Sodium Thiosulphate and Dilute Hydrochloric Acid
The aim is to find out if changing the concentration of the hydrochloric acid solution has an effect on the time taken for the reaction. The reaction that will take place is: Hydrochloric acid + Calcium Carbonate + Calcium Chloride + Water + Carbon dioxide 2HCl (aq) + CaCo3 (s) CaCL2 (aq) + H2O + CO2 (g). Collision theory - Collisions between reactant particles are needed. for the reaction to take place in order to form a product.
The gradient of the graph tells us whether the different rate curves have the same relation, meaning if they have a similar rate of reaction. Reactions can take place in a variety of customs; they can bee steep or steady. The steeper the slope, the faster the reaction takes place. The steadier the slope, the slower the reaction takes place. Aim:
The first experiments investigate the order of reaction with respect to the reactants; hydrogen peroxide, potassium iodide and sulphuric acid by varying the concentrations and plotting them against 1/time. An initial rate technique is used in this experiment so ‘the rate of reaction is inversely proportional to time.’ To find the order of reaction in respect to the reactants, 1/time is plotted against the concentration of Hydrogen Peroxide using the equation:
rate of reaction. To do this I will put a piece of paper with an "X"
Hydrochloric acid + calcium carbonate arrow calcium chloride + carbon dioxide + water. HCl(aq) + CaCO3(s) arrow CaCl2(aq) + CO2(g) + H2O(l) Things that affect the reaction rate of this experiment are: 1. The temperature of the hydrochloric acid. 2.
The Effect of Concentration of Hydrochloric Acid on the Rate of Reaction with Magnesium Aim: To investigate the effect of concentration of hydrochloric acid on the rate of reaction with magnesium Prediction: As the concentration of the hydrochloric acid increases, so will the rate of reaction Hypothesis: In a reaction, particles of two different reactants react together to form a product. The reaction only takes place on account of two things, if the particles collide, and if the collision has enough 'activation energy'. The two reactant particles, in this case magnesium particles and hydrochloric acid particles, must collide with each other on the correct 'collision course'. If this does not occur then no chemical reaction will take place. The reaction must also have enough energy, this can be affected by temperature, the more heat the particles have the faster they move and so the more energy therefore more chance of successful collisions.
The Effect of Temperature on the Rate of Reaction Between Hydrochloric Acid and Calcium Carbonate
An investigation into how changing one variable influences the rate of reaction between marble chips and dilute Hydrochloric acid
If they collide with sufficient energy, then they will react. The minimum amount of kinetic energy required for particles at the time of collision is called the activation energy and this theory is known as the?collision theory?. Reactions occur in all circumstances. Chemicals are always combining and breaking up. Reactants and products combine and break apart in all reactions.