LAB: Some Metals Are More Reactive Than Others

Aim: To conduct fair tests/experiments with iron, aluminium, copper, magnesium, and zinc, and to use the results to rank the metals in order of reactivity, from the most reactive metal, to the least reactive metal .


Variables Table of Reactivity Test between 5 Different Metals


What is/are
the
Variable?

How will it be changed?
How will it be measured?
How will it be controlled?

Independent Variable
Type of Metal
5 different types of metals; iron, copper, magnesium, and zinc.
Dependent Variable
Reactivity of metals added to hydrochloric acid
Use a camera to record the reactions of the each metal being added to 6ml of hydrochloric acid.
Controlled variables / Constants
Amount of metal
Use 0.7 grams of each metal throughout the expirement
Form of metal
Only use non-powder form of each metal.
Same testing time
Use the camera to measure 2 minutes of testing time.
Liquid added to metals
Using 6ml of hydrochloric acids for each metal to be added to.

Hypothesis

If iron, aluminum, copper, zinc, and magnesium is added to hydrochloric acid, then magnesium would be the most reactive metal and because it is a alkaline earth metal and it is the metal furthest from the noble gases in the periodic table, making it reactive. aluminum will be the least reactive metal because people use aluminum foil to preserve it and it doesn’t have any reactions to the food.


Materials/Equipment:

    • camera
    • 0.7g of iron, aluminum, zinc, magnesium and copper in non powdered form.
    • 5 Test tubes
    • Hydrochloric acid
    • Graduated cylinder
Method
    • 1. Gather all materials/safety equipment.
    • 2. Use a scale to measure each the metal to have the the same mass; 0.7g.
    • 3. Lable the five test tubes according to the mixture to prevent making observations for the wrong metal.
    • 4. Pour 6ml of hydrochloric acid into a graduated cylinder, after this, pour 6ml of hydrochloric acid from the graduated cylinder to the test tube.
    • 5. Add 0.7 of iron into the hydrochloric acid
    • 6. Leave the iron to rest for 2 minutes. Be sure to record observations.
    • 8. Repeat steps 4-7 for the other four metals. Be sure to take videos of the expirement.
    • 10. Clean experiment area
Diagram_of_Appuratus.JPG

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Thoughts on your wiki Andrea_Law Andrea_Law 0 42 Dec 16, 2009 by Andrea_Law Andrea_Law
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Observations for Reactivity of Iron, Zinc, Magnesium, Copper and Aluminum

Metal
Quantitative Observations
Magnesium
#1

Gas (bubbles rising from aluminum foil), solid, grey, odourless, opaque, temperature remains the same.
Zinc
#2
Solid (zinc), gas (bubbles of all sizes rising), temperature remains the same.
Aluminum
#3

Gas; bubbles cover iron, solid (iron), liquid (hydrochloric acid), grey, hydrochloric acid changes from white/transparent to a light shade of grey odourless, opaque, temperature remains the same.
Iron
#4

Liquid (dissolved magnesium, and hydrochloric acid), gas (steam rising from test tube), magnesium immediately reacted by dissolving, having steam rise, and by the change of temperature.
Copper
#5

Gas (bubbles of which some over the copper, some coming from the test tube), solid (copper), liquid (hydrochloric acid), form/shape remains the same, temperature remains the same, colour remains the same; bronze.
Conclusion
The experiment shows that out of iron, magnesium, copper, zinc and aluminum, magnesium was the most reactive and copper was the least reactive. Zinc was second, aluminum was third, and iron was fourth. This ranking was based on the observation: magnesium dissolved immediately after being dropped to the hydrochloric acid and copper had very little bubbles came up. All the others were in between in amount of bubbles going up and the amount of bubbles covering the metal.
The results support the hypothesis for the most reactive metal; however, the hypothesis for the least reactive metal was incorrect. The hypothesis states that aluminum would be the least reactive metal but it was the 3rd reactive in the experiment and copper turned out to be the least reactive.
The data is similar to the data of published work because all of the published work say that magnesium is one of the most reactive metals because it’s ion makes it bond easily with common elements such as hydrogen, chloride, and oxygen. The published work also tells us that copper is one of the least reactive metal s
Magnesium was the most reactive metal out of all of the 5 metals because it is part of a low group of the periodic table, and because magnesium is an alkaline earth metal with +2 electrons so it could be easily reactive with elements such as oxygen, chlorine, and hydrogen. "You could argue that the activation energy will fall as you go down the Group and that will make the reaction go faster" (Reactions of the Group).

Magnesium reacts with hydrochloric acid to make an acid salt of magnesium and hydrogen. “This reacts with hydrochloric acid (and virtually all other acids) to form the acid salt of magnesium and hydrogen: Mg + 2HCl = MgCl2 + H2” (Crichton). [Not finished]


Evaluation
1. It is not very reliable due the weaknesses as shown in the table below, and due to the fact of how the experiment was completed once.

2. The method was valid to collecting the data of the reactivity with hydrocloric acid and 5 different metals, excluding the safety steps, which are not as valid to collecting the data, however is more important for the lab workers safety.

3. Weaknesses and Improvements of Reactivity Experiment With Hydrochloric Acid and 5 Different Metals
Weaknesses
Improvements
- Not all metals had exact weight planned chosen and recorded in method due to lack of small metal pieces.
- Use powder form for each metal therefore can measure exact weight chosen and recorded in the method.
- Test tubes could not be labeled due to lack of permanent markers, and due to the ink smudges of the pen used.
- Use permenant marker, say specifically in method.
- Too much hydrochloric acid was added to the aluminum due to the lack of acid to react to the aluminum, thus effecting the reactivity of hydrochloric acid and aluminum.
- Use powder form for every metal therefore remaining fair test, and therefore being able to react properly with hydrochloric acid.
4. As shown in the table above, there were weaknesses that made this test unfair, however there were factors of which made this test fair. The same lab worker recorded observations, this may have effected how fair this tes was due to some observations which may have been opinionated,

Works Cited
""Reactions of the Group 2 Elements with Air or Oxygen." ChemGuide. N.p., n.d.
Web. 16 Dec. 2009. <http://www.chemguide.co.uk/inorganic/group2/
reacto2.html>. Reactions of the Group 2 Elements with Air or Oxygen." ChemGuide. N.p., n.d.
Web. 16 Dec. 2009. <http://www.chemguide.co.uk/inorganic/group2/
reacto2.html>.
Crichton, Trevor. "Magnesium Expirement." Finishing. N.p., n.d. Web. 16 Dec.
2009. http://www.finishing.com/123/26.shtml.