Science Coursework – What factors effect the rate of reaction between magnesium and hydrochloric acid?
Background Knowledge
There are four factors that can affect the rate of reaction and they all rely on the collision theory. This is basically how hard and how often particles collide with each other. The more and harder they collide, the faster the reaction time will be.
If the acid is made more concentrated there are more particles, which means collisions are more likely. So, the higher the concentration, the quicker the reaction time is.
Temperature also affects the rate of reaction. If the temperature is increased, the particles move quicker so more collisions happen. This means the higher the temperature, the
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The last factor that increases rate of reaction is the surface area.
Grinding up the magnesium into a powder increases the surface area, so the acid has more space to react on. This means the larger surface area, the quicker reaction time.
Magnesium reacts very strongly with hydrochloric acid. In a high concentration of acid it can take just a few seconds for magnesium to furiously bubble and finally completely dissolve with no trace except for hydrogen gas.
Equation of magnesium and hydrochloric acid:
2 HCl+ + Mg [IMAGE]Mg2+ + H2
Measuring rates of reaction
In this investigation there are two experiments that can be used to test rates of reaction.
Using a gas syringe
As more gas is produced the plunger inside the syringe moves out of the syringe so the gas can be measured by marks on the syringes length. I would have to measure the amount of hydrogen produced in regular intervals which would change for each concentration. Again, I would need approximately six or seven results to create enough points to put on a graph graph.
Collecting Gas using a Syringe
Equipment needed:
-Scales;
-Conical flask;
-Gas syringe;
-Stand with clamp;
-Hydrochloric acid (30 ml);
-Magnesium strip (2cm long);
-Rubber tube with bung.
The graph will have an independent variable and a dependant variable.
The independent variable being fixed intervals of time on the x-axis,
2. Obtained a 2-3 cm strip of magnesium metal ribbon and coiled it loosely into a small ball. Added the magnesium metal to the acid in the test tube.
During the immersion of the magnesium metal in the hydrochloric acid solution, white bubbles could be seen escaping the surface of the metal as gas was produced during the reaction. Depending on the temperature of the hydrochloric acid and the overall molar concentration, the rate of reaction differed but the same signs were shown. During the reaction between the magnesium metal and higher concentrations of hydrochloric acid, it was observed that the test tube grew quite warm to the touch. As the immersed magnesium strip sank down, it appeared coated in a layer of white bubbles that fizzed like a carbonated drink. In the lower concentrations of hydrochloric acid, the strip spent some time floating at the surface of the solution in the test tube, later sinking down to the bottom as the
3. The third source of error is not knowing for how long to exactly heat the magnesium until it no longer ignites and forms into a white powder of magnesium oxide. In the procedure, it is stated for how long to heat the magnesium, but as the lab went on, it is realized that the magnesium had to be heated for a longer time. This could mean that the magnesium could have been not heated long enough or too little for it to be fully converted into the magnesium oxide product effecting the final results of the lab by having smaller
always give out or take in energy most of the time this is heat energy
Rate of reaction between Hydrochloric Acid and Calcium Carbonate Calcium carbonate reacts with hydrochloric acid to form carbon dioxide gas. One way of following the rate of reaction at which it reacts is to measure the volume of carbon dioxide produced at certain time intervals during the reaction. CaCO + 2HCl CaCl + H O + CO = = =
In this lab, a calorimeter was used to find the enthalpy of reaction for two reactions, the first was between magnesium and 1 molar hydrochloric acid, and the second was between magnesium oxide and 1 molar hydrochloric acid. After the enthalpy for both of these were found, Hess’ law was used to find the molar enthalpy of combustion of magnesium, using the enthalpies for the two previous reactions and the enthalpy of formation for water. The enthalpy of reaction for the magnesium + hydrochloric acid reaction was found to be -812.76 kJ. The enthalpy of reaction for the magnesium oxide + hydrochloric acid reaction was found to be -111.06 kJ. These two enthalpies and the enthalpy of formation for water were manipulated and added together using Hess’s law to get the molar enthalpy of combustion of magnesium. It was found that the molar enthalpy of combustion of magnesium was -987.5 kJ/mol. The accepted enthalpy was -601.6 kJ/mol, which means that there is a percent difference of 64%. This percent difference is very high which indicates that this type of experiment is very inefficient for finding the molar enthalpy of combustion of magnesium. Most likely, a there are many errors in this simple calorimeter experiment that make it inefficient for finding the molar enthalpy of combustion of magnesium.
Three factors that can affect the rate of reaction are temperature, pH and the salinity.
Question: How does changing enzyme concentration or temperature affect the reaction time of enzyme activity?
I could use a gas syringe to collect the gas that will evolve from my
About 80 mL of HCl was obtained and mixed with phenolphthalein. Using a LabQuest unit and Gas Pressure Sensor kit, the HCl mixture was added to the flask with the magnesium ribbon and allowed to react. When reaction was complete, the change of temperature and gas was recorded. This procedure was repeated for different masses of magnesium ribbon (masses found on page 89 of the lab manual). After the completed procedure, moles of H₂ produced in each trial were calculated. (The actual procedure can be found on pages 87-89 of the lab manual)
The aim of the experiment will be to investigate how varying water temperatures influence the time of a chemical reaction, in this case being, a combination of Sodium Thiosulfate and Hydrochloric Acid.
Introduction: Chemical reactions are dependent upon two factors: temperature and concentrations of substance. We can monitor the rate at which a chemical decomposes or the rate at which a chemical substance appears. In this experiment we will be measuring the rate of decomposition of hydrogen dioxide with the following reaction:
One of our flaws was that the temperature of the water was not exactly the same when we did the different trials. The temperatures were slightly off from our recorded value during the experiments. The change in temperature would affect the time it took for the Alka-Seltzer tablet to dissolve in the water. If there was a direct relationship between water temperature and dissolve time, we would not be able to see it because the temperatures are off and the dissolve times are not associated with the correct temperature. Another flaw is that we did not use the same amount of water throughout the experiment. We used a beaker to measure the water, which did not result in accurate measurements. The difference in amount of water could result in a difference in reaction time. The third flaw in the experiment was that during the reaction of the warm water, the water in the cup overflowed and spilled, bringing some of the Alka-Seltzer tablet with it. There were different amounts of tablet in different areas of the water, which means a different amount of Alka-Seltzer remained inside of the cup in each trial. This difference would mean that data for the warm water would fluctuate and we would not have accurate
In this experiment the scientists are looking for how gas production is effected when different sized Alka-Seltzer tablets are put into water. The independent variable is the different sizes while the dependent variable is the amount of gas produced. A constant variable includes the same brand of Alka-Seltzer tablets, the volume of water and same starting temperature. Finally the scientist’s control variable is the first trial testing the whole tablet comparing its reaction time to each new piece.
For our lab, we have six beakers of water. Three of the beakers contain high temperature water that range from 46 ℃ to 55 ℃, while the other three beakers contain room temperature water that range from 22 ℃ to 23 ℃. Then, we take six different colored Alka Seltzer tablets, and place them into the beakers one at a time. We record the length of time it takes for each Alka Seltzer to dissolve