center5938221By Karissa Wilson
Year 10, 2018
4000020000By Karissa Wilson
Year 10, 2018
right1445260Investigation into factors that effect the rate of the reaction between Hydrochloric acid and magnesium ribbon
Background Information PAGEREF _Toc513292433 h 2What is a Chemical Reaction? PAGEREF _Toc513292434 h 2Types of Chemical Reaction PAGEREF _Toc513292435 h 2Decomposition Reaction PAGEREF _Toc513292436 h 2Combustion Reactions PAGEREF _Toc513292437 h 2Combination Reactions PAGEREF _Toc513292438 h 2Redox Reactions PAGEREF _Toc513292439 h 3Corrosion Reactions PAGEREF _Toc513292440 h 3Displacement Reactions PAGEREF _Toc513292441 h 3Precipitation Reactions PAGEREF _Toc513292442 h 3Rates of Chemical Reaction PAGEREF _Toc513292443 h 3Aim PAGEREF _Toc513292444 h 4Hypothesis PAGEREF _Toc513292445 h 4Variables PAGEREF _Toc513292446 h 4Independent PAGEREF _Toc513292447 h 4Dependent PAGEREF _Toc513292448 h 4Controlled PAGEREF _Toc513292449 h 5Risk Assessment PAGEREF _Toc513292450 h 5Materials PAGEREF _Toc513292451 h 5Procedure PAGEREF _Toc513292452 h 6Results PAGEREF _Toc513292453 h 6Discussion PAGEREF _Toc513292454 h 7Conclusion PAGEREF _Toc513292455 h 8Evaluation PAGEREF _Toc513292456 h 8References PAGEREF _Toc513292457 h 8Background informtion
What is a chemical reaction?
A chemical reaction is a process in which one or more substances, the reactants, are converted to one or more different substances, the products. Substances are either chemical elements or compounds. A chemical reaction rearranges the constituent atoms of the reactants to create different substances as products (Encyclopedia, Britannica, Inc, 2018).
Law of conservation of mass
The law of conservation of mass states that mass can neither be created or destroyed only transferred (Britannica School, 2018). This specific law is very important to scientists when conducting experiments or writing reports, more specifically chemical equations. However, when understanding chemical reactions scientists need to know the mass so they can correctly attempt the chemical equations and so the relevant information is correct. A simple chemical equation would be; The mass of the products in a chemical reaction is equal to the mass of the reactants. There are no more atoms at the end of the chemical reaction than there were at the beginning (Amrita Vishwa Vidyapeetham & CDAC Mumbai).
Na+Cl2 NaClTypes of chemical reactions
A decomposition reaction occurs when one reactant breaks down into two or more products (CK-12 Foundation, 2018). An example of everyday decomposition reaction would be when we open soft drink because the air reactions creating fizzing.
An example of a decomposition reaction with carbonic acid would be would be:
H2+CO3 H2O+CO2Redox Reaction
Redox reaction is named after the two processes that occur during it, reduction and oxidation CITATION Lin12 l 3081 (Linstead, 2012). Reduction is when atom, molecule or ion gain electrons and oxidation is when they lose electrons CITATION Bri18 l 3081 (Britannica School, 2018) CITATION Lin12 l 3081 (Linstead, 2012).
A redox chemical equation is;
C+O2 CO2Combustion Reaction:
Combustion reactions always involve molecular oxygen (O2). Anytime anything burns, it is a combustion reaction. Combustion reactions are almost always exothermic meaning they give off heat. When organic molecules combust the reaction, products are carbon dioxide and water as well as heat. For example, the fire produced by gas stoves is an example of combustion in our everyday lives.
A common example of a combustion reaction is
hydrocarbon + oxygen ? carbon dioxide + water.
Corrosion reactions are reactions where metal reacts with substances in the air or water and is corroded away CITATION Bri18 l 3081 (Britannica School, 2018). Rusting is an iron oxide, its red and forms due to moisture and pressure. It happens over time and happens in everyday lives you, you may see rust places including cars, boats, trailers and bikes.
A simple chemical equation for iron rusting is
Fe+O2 Fe2O3Displacement reaction
Displacement reaction is a chemical reaction in which a more reactive element displaces a less reactive element from its compound. Both metals and non-metals take part in displacement reactions (Amrita Vishwa Vidyapeetham & CDAC Mumbai).
A precipitation reaction refers to the formation of an insoluble salt when two solutions containing soluble salts are combined. The insoluble salt that falls out of solution is known as the precipitate, hence the reaction’s name. Precipitation reactions can help determine the presence of various ions in solution. An example of a precipitation reaction in everyday lives is when rings in bathtubs form, this normally occurs when the water is hard. This reaction is due to the large amounts of calcium or magnesium ions in the solution.
Rates of Chemical Reactions
We have many amazing things that include science in our everyday lives. Our body system consists lots of biological reactions. If a biochemical reaction in our body is too fast or too slow, it can endanger our life. If the certain medicine releases heat during reaction in our body, it is important to make the reaction is slower, therefore ensuring the patient will not experience high fewer during medication. Our body needs to have the correct speed to decompose the medicine. Other examples would be cooking and cleaning. The rate of chemical reactions determines how long it will take to cook food. By slowing the rate of reaction between microbes we can slow the process of food, making this unpleasant to eat.
Many other factors exist when it comes to changing the reaction rate. Reaction rates can be affected by many different factors like surface area, temperature, concentration of reactants or nature of the reactants. If there is a lower heat, the energy threshold is a lot higher. If the temperature is increased, then the concentration of a dissolved reactant is also increased along with the pressure. For a chemical reaction to occur, the reactant particles must collide. By changing the concentration and pressure there are more reactive particles in the same volume. There becomes a greater chance of them colliding meaning the reaction rate increases. If we change the particle size, then the surface area is increased. If more particles are exposed there becomes a higher chance of colliding particles. Although, if we change the temperature then the particles all move more rapidly. All of these increase the reaction rate by making the particles collide together more rapidly. If the gas particles are all pushed together then the size of the surface area is significantly larger.
The aim of this experiment was to investigate how surface area can affect the rate of reaction between hydrochloric acid and magnesium ribbon.
If the temperature of the hydrochloric acid is increased, then the rate of the reaction with magnesium is also increased. Then if a magnesium strip is combined with hydrochloric acid and another magnesium ribbon is added to the same amount of liquid but a larger surface area then the ribbon will dissolve more rapidly. This is because the particles are holding much more heat resulting them to collide more frequently. When they collide, they break the chemical bond between the hydrogen and chloride.
IndependentThe independent variable that was changed was the boiling water and the ice cubes.
DependentThe dependent variable that was measured was the time it took for the magnesium ribbon to completely dissolve.
ControlledThe controlled variables that were kept the same was the total mass of magnesium and the amount of hydrochloric acid.
All experiments carry a risk and all materials and substances have to potential to cause harm. The specific experiment we conducted was at a medium risk. General safety precautions must constantly be considered before conducting an experiment. Laboratory coats, safety goggles and gloves are should always be worn. The materials that have safety hazards include the boiling water, broken glass and spilling the hydrochloric acid. When handling boiling water you should always wear “hot-hands” to ensure you don’t burn yourself. When using any equipment, you should inspect it first to make sure it has no damage. For example, if a beaker has a chip it could break even more and go into somebody’s hand, if you see a damaged piece of glass you should report it to the teacher and dispose of it in a glass bin. One of the risks that pose a large safety hazard is spilling the chemicals. Spilling the hydrochloric acid could be very severe in burning someone’s skin or even corroding someone’s eye. All of these pose a large risk and we take all safety precautions to avoid danger hazards and to ensure we conduct the experiment as safe as possible.
Risk Danger Precaution Taken
Spilling hydrochloric acid Could severely cause burns Lab coat, safety glasses and gloves were worn.
Broken glass Cuts The glass was inspected before use and if it was chipped or broken glass it would disposed of in a glass bin.
Test tube rack
Ice cream container
Retort stand and clamp
1M hydrochloric acid
Test tube with delivery tube
ProcedureSafety goggles, gloves and lab coats were put on.
Oxide coating was removed from magnesium ribbon with sand paper.
10mL of hydrochloric acid was measured in a measuring cylinder and then poured into a test tube.
2cm of a Magnesium ribbon was dropped into test tube and stopwatch was immediately started.
Stopwatch was immediately stopped when the ribbon was completely dissolved.
The reaction time was recorded in minutes and seconds and was put in a result table.
Steps 1-7 were repeated.
Table 1: Preliminary Test for Rate of Reaction of Magnesium and Hydrochloric Acid
Name of reactant 1 Name of Reactant 2 Product Reaction Time (m) Observations
2cm magnesium ribbon 10 mL of hydrochloric acid Magnesium chloride and hydrogen 1:58 Rapid bubbling when magnesium was first dropped
Test tube was warm to touch during reaction
Pressure went up to 145 (kpa) and dropped
Table 2: The Effect of Changing the Surface Area of Magnesium on the Rate of Reaction Between Hydrochloric Acid and Magnesium
Trial Temperature Time (Mins) Observations
1 0 degrees 7 minutes Took a long while to dissolve
Bit of fogginess
2 5 degrees
6 minutes Rapid bubbling when magnesium was first dropped
Test tube was warm to touch
Air above test tube looked foggy
5 minutes ” ”
4 minutes Weird odour
Foggy white gas
3 minutes ” ”
2 minutes ” ”
2 minutes ” ”
2 minutes ” ”
2 minutes ” ”
1 minute ” ”
center617838Line graph of results:
A word equation for the reaction of magnesium and hydrochloric acid:
magnesium+hydrochloric acid magnesium chloride+hydrogenWhen magnesium was placed in the hydrochloric acid it imminently fizzed. A gas then was produced therefore, assuming this was because of the different energy levels they have. The less concentrated it was, the slower the ribbon oxidized, creating less fumes and the more it oxidized the more fumes were present. although magnesium is more reactive than hydrogen it was displaced during the chemical reaction, resulting in hydrogen gas being released from the tube.
A specific type of metal can displace a less reactive metal from its compounds. The chemical reaction takes place when the magnesium ribbon is dropped into the hydrochloric acid. This is a single replacement reaction is a common example of a metal reacting in an acid to release hydrogen gas, because (hydrogen) was removed from the chloride and replaced by magnesium this is a single displacement reaction.
It was evident that a chemical reaction between magnesium and hydrochloric acid took place. through the experiment magnesium was dissolved. The atoms in magnesium bonded with the ones in chloride making the solution a white colour. As a result of this hydrogen gas was released meaning that it broke its bond from chloride.
Changing the independent variable affected the test significantly. In our test the independent variable was the ice cubes and boiling water. The results table shows that the colder the temperature was the longer it took, meaning the particles were not colliding as much. Whereas an example of 80 degrees Celsius took 1 minute for the ribbon to dissolve because of how rapidly the particles were colliding. We were constantly changing this and as a result we had a fair text of every 10 degrees with the time going down by just one minute each time.
The temperature and the length of the magnesium ribbon were large factors whilst conducting this experiment because they both contributed to the reaction rate. Whilst the temperature changed so did the time the higher the temperature was the lower the time and vice versa.
My hypothesis states what the table of results says meaning it was correct, the aim of this experiment was also achieved. When the temperature was 80 degrees Celsius it only took 1 minute to dissolve a 2cm piece of magnesium ribbon. At 10 degrees Celsius it took 5 minutes because the particles weren’t colliding and reacting as fast as they were with the major heat.
At the start of the preliminary test we carried out the procedure that we thought would be the best to get the most accurate results. We cut a 2cm magnesium ribbon and placed it in 10 ml of hydrochloric acid, we then placed the tester on top and watched the timer to ensure we stopped it when it was dissolved. We noticed that the least fair part of the test was where we had to remove the oxide coating from the magnesium ribbon. Realising that it was not fair because we had a different amount of coating on each strip. To overcome this, we tried out hardest to sand all the coating off to ensure this was a fair test by sanding them all at once.
BIBLIOGRAPHY Britannica School. (2018). Chemical reaction. Retrieved April 24, 2018, from https://school.eb.com.au/levels/high/article/chemical-reaction/110109
Linstead, G. (2012). Peasron Science S.B. 10 (3rd ed.). Melbourne: Pearson Australia.
Lofts, G., & Evergreen, M. J. (2017). Jacaranda Science Quest 10 Australian Curriculum (3rd ed.). Brisbane: John Wiley & Sons Australia, Ltd.
ThoughtCo. . (n.d.). Retrieved from https://www.thoughtco.com/examples-of-chemical-reactions-in-everyday-life-604049