Activity Series of Metals Lab

by honeybooboo (student)

Activity Series Lab-2012

Introduction

The types of changes that occur during these tests are chemical changes. Chemical changes will usually be tough to reverse, a new substance is created, heat is released, light is released, a solid is made (precipitate,) gas produced or the solution changes in colour. These chemical changes can be cause by decomposition, combustion, synthesis, single displacement or double displacement. The type of reaction that occurs during the tests is a single displacement reaction. This means that one element replaces another element in a compound. The general equation used for this reaction is A + BC -> B + AC. Like most other chemical changes single displacement reactions cannot be reversed. Depending on the activity series of metal some elements will be able to displace the other metal in the compound and some may not.

Single Displacement reactions occur according to the Activity Series of Metal. Based upon experimental evidence reactive metals have been placed in order of reactivity known as the activity series of metal. The activity series is a chart with the most reactive metals on the top and the least reactive metals on the bottom. Lithium is on the top meaning it is the most reactive whereas gold is on the bottom being the least reactive. The order of the metals from most to least reactive corresponds with how easily the metals can replace hydrogen from acids and water. A metal will displace any metal below it on the activity series chart. This is how the outcome can by hypothesised.

As these chemical reactions occur the energy changes in chemical. In a chemical reaction, bonds are built and broken; chemical bonds are sources of stored energy. Breaking bonds requires more energy whereas creating bonds releases energy. An exothermic reaction occurs when the energy need to break the bond in the reactant is less than the energy released upon the formation of products. In an exothermic reaction heat if release. However Endothermic is the complete opposite, the energy required to break bond in the reactant is greater than the energy released upon the formation of the product. This reaction will feel cold.

Purpose:

To verify that the Activity Series of Metals is valid and 100% accurate and ensure it is truthful about the ability an element has to react and replace another element due to its reactivity and order of the series. This is tested by placing metals into ionic compound aqueous solutions to see if a chemical reaction occurs.

Hypothesis

The tests 2, 5 and 9 were predicted to show no chemical reaction at all. This is due to the fact that according to the activity series of metal, the lone metals were not able to displace the metals in the ionic compounds. The lone metals are lower on the activity series of metal than the metals in the ionic compounds causing the chemical reactions to be not possible.

Materials

10 test tubes
10 beakers
test tube rack
sand paper
Metals:
10 aluminum pieces
2 iron nails
10 zinc pieces
5 magnesium pieces
5 copper pieces

This is a preview of the whole essay

Materials

10 test tubes
10 beakers
test tube rack
sand paper
Metals:
10 aluminum pieces
2 iron nails
10 zinc pieces
5 magnesium pieces
5 copper pieces
5 tin pieces
5 lead pieces
Solutions:
10 mL of copper (II) chloride
10 mL of magnesium chloride
20 mL of lead (II) nitrate
10 mL of cobalt (II) chloride
10 mL of calcium nitrate
10 mL of tin (II) chloride
10 mL of silver nitrate
10 mL of zinc chloride
10 mL of copper (II) sulfate

Observation:

See attached Table.

Analysis

In test number 1, a single displacement reaction was predicted to happen due to the Activity Series of Metal. The aluminum would displace the copper in the solutions. This will occur because aluminum has a higher placement and is more reactive on the activity series of metals than copper. The prediction was proven true and the aluminum chip began to develop a copper layer.

In test number 2, a single displacement reaction was not predicted to happen due to the Activity Series of Metal. The iron would not displace the magnesium in the solutions. This will occur because magnesium has a higher placement and is more reactive on the activity series of metals than iron. However the prediction was proven false and the nail began to develop orange layer or rust.

In test number 3, a single displacement reaction was predicted to happen due to the Activity Series of Metal. The zinc would displace the lead in the solutions. This will occur because zinc has a higher placement and is more reactive on the activity series of metals than lead. The prediction was proven true and the zinc began to break apart and start to become a black powder.

In test number 4, a single displacement reaction was predicted to happen due to the Activity Series of Metal. The magnesium would displace the cobalt in the solutions. This will occur because magnesium has a higher placement and is more reactive on the activity series of metals than cobalt. The prediction was proven true and the magnesium began to develop a dark navy blue green layer.

In test number 5, a single displacement reaction was not predicted to happen due to the Activity Series of Metal. The zinc would not displace the calcium in the solutions. This will occur because calcium has a higher placement and is more reactive on the activity series of metals than zinc. The prediction was proven true and no reaction occurred.

In test number 6, a single displacement reaction was predicted to happen due to the Activity Series of Metal. The aluminum would displace the tin in the solutions. This will occur because aluminum has a higher placement and is more reactive on the activity series of metals than tin. However the prediction was proven false and no reaction occurred.

In test number 7, a single displacement reaction was predicted to happen due to the Activity Series of Metal. The copper would displace the silver in the solutions. This will occur because copper has a higher placement and is more reactive on the activity series of metals than silver. The prediction was proven true and the copper began to develop a gray drown precipitate.

In test number 8, a single displacement reaction was predicted to happen due to the Activity Series of Metal. The tin would displace the lead in the solutions. This will occur because tin has a higher placement and is more reactive on the activity series of metals than lead. However the prediction was proven false and no reaction occurred.

In test number 9, a single displacement reaction was not predicted to happen due to the Activity Series of Metal. The lead would not displace the zinc in the solutions. This will occur because zinc has a higher placement and is more reactive on the activity series of metals than lead. The prediction was proven true and no reaction occurred.

In test number 10, a single displacement reaction was predicted to happen due to the Activity Series of Metal. The iron would displace the copper in the solutions. This will occur because iron has a higher placement and is more reactive on the activity series of metals than copper. The prediction was proven true and the iron has developed a layer of copper.

Results and Discussion

The activity series of metal chart was fairly accurate. Most tests were proven true to the predictions made due to the activity series of metal chart. Out of the total of 10 tests there were 3 tests that were proven false compared to our prediction. The Iron and Magnesium chloride test was predicted to not react. However a reaction was present. It was predicted to not have a reaction because iron is 4 metals below magnesium on the activity series of metals chart. An unpredictable reaction occurred. This could be the iron displacing the magnesium however this is very unlikely and slightly impossible. The Iron nail started to rust and due to some research, rust is created when a reaction between the iron and oxygen while it is exposed to moisture or water. The rust on the iron nail was formed because the nail reacted with the oxygen and the other gases in the atmosphere while it is in the aqueous ionic compounds solution. In order to improve this lab we could avoid the source of error. We could place our experiment in a contained environment or minimized the amount of oxygen that may come into contract with the solution by covering the top if the test tube or removing the test tube and placing it in an environment where oxygen is minimal. Or reduce the amount of time or level of exposure of the nail to oxygen to decrease the possibility of rusting.

The second test that was proven false against the hypothesis was aluminum and tin chloride. It was predicted to have a reaction because aluminum is 7 metals higher than tin on the activity series of metals. A reaction did not occur. There was probably a reaction that was occurring however it was a slow process and when our observations were recorded the reaction has not fully reacted. 24 hours was probably too short of a period time to determine if there is a chemical reaction present. To avoid this error from occurring again, the period of observation should be extended and observations should be taken more than once to see the gradual change.

The last test that was proven false against the hypothesis was tin and lead (II) nitrate. It was predicted that there would be a reaction because tin is right above lead. No reaction ended up occurring. There was most likely a reaction however the reaction may once again be unnoticeable or did not fully react within the 24 hours. 24 hours was probably too short of a period time to determine if there is a chemical reaction present. To avoid this error from occurring again, the period of observation should be extended and observations should be taken more than once to see the gradual change.

Any tests that were proven false against the hypothesis may just be the experimental errors that occur and the setting of which the experiment was performed in. For example the time the experiment was observed for was not long enough to notice change for some of the tests and oxidization occurred to cause an unwanted reaction with the lone metals. Minimizing the exposure to the atmosphere or oxygen can affect the results and also a rubber stopper may also be useful to control the amount of oxygen from entering the tests.

Conclusion

The Activity Series of Metal is very accurate and reliable when used to predict if a certain reactive metal will replace other metals within an ionic compound through chemical reactions. The chart can be referred upon when making predictions about the products from a certain set of reactants in a single displacement reaction and maybe even a double displacement reaction. The Activity Series of Halogens may also be just as helpful for displacement of halogens. This lab confirmed the reliability of the Activity Series of Metal by placing metals into different aqueous solutions to see if a displacement occurred through single displacement reaction. Even though some tests were proven false against the prediction made with the Activity Series of Metals, the results were probably altered due to the experimental errors made. These errors made, may have effect the results. The most important finding is that the Activity Series of Metal is only 100% accurate in a controlled environment where other gases and interference is not possible to cause unwanted reactions.

References

Clancy, C. (2001). McGraw-Hill Ryerson chemistry 11. Whitby, Ont.: McGraw-Hill Ryerson.

Hathaway, J. (2012). Chemistry 11U Notes. Bradford: Bradford District High School. J. Hathway