Trends In Reactivity PDF

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Trends In Reactivity full lab report with graphs ...

Description

Name: Text

Partner: Text

Date: 03/05/2020

Section: 29

Instructor: Dr. Fellows Trends in Reactivity Experiment Introduction: The experimental purpose in part one is to show the reactivity to most metals found on the periodic table. The metals are first tested in water, those that react to the water are found to have higher levels of reactiveness. The metals that did not react with the cold water are then tested using a cold acid. The metals that reacted with the cold acid are the next tier of reactive metals, and they fall midline in terms of reactiveness. The final metals that did not react with cold water nor cold acid, are then placed in a hot water bath in hopes the metals will produce a reactivity to hot acid. The least conductive metal we found to be copper, which had no visible reactivity. The experimental purpose of part two was to test the reactivity of halogens and analyze their position on the periodic table. Chlorine, Bromine and Iodine were tested. Two samples of each halogen was obtained and tested with the two opposite substances, meaning we did not mix the same halogen together. Chloride was found to be the most reactive, bromine came in second, and Iodine was found to be the least reactive.

Reactivity of Metals with Water and Acid Metal

Cold Water Results

Cold Acid Results

Hot Acid Results

Aluminum (Al)

Slightly Reactive

Very Reactive

Not Observed

Calcium (Ca)

Very Reactive

Not Observed

Not Observed

Copper (Cu)

Not Reactive

Not Reactive

Not Reactive

Iron (Fe)

Not Reactive

Slightly Reactive

Very Reactive

Lead (Pb)

Not Reactive

Slightly Reactive

Most Reactive

Magnesium (Mg)

Slightly Reactive

Not Observed

Not Observed

Tin (Sn)

Not Reactive

Not Reactive

Slight Reaction

Sodium (Na)

Most Reactive

Not Observed

Not Observed

Zinc (Zn)

Not Reactive

Very Reactive

Not Observed

Metal Ranking from Most to Least Reactive 1 Most Na

2 Ca

3 Mg

4 Al

5

6

Zn

7

Fe

8

Sn

9 Least

Pb

Cu

Reactivity of the Halogens Cl2 Cl1-

I2

Br2 Yellow Coloring

Stayed Orange

Wine Color

X

Pink/Wine

Br1-

X

I1-

Most Reactive

Cl2

Least Reactive

Br2

I2

Oxidation anf Reduction Formulas Reduced

Oxidized

Cl2 + Br1- ⇾Cl-1 + Br02 Oxidized

Cl0 + I- ⇾ I2 + ClReduced

Br2 + Cl- ⇾ NR

Discussion: Overall the experiment was straight forward and the results were quickly seen. I felt that testing the reactivity of the metals was easier than the halogens. Testing the halogens required a vigorous amount of mixing that was not outlined in the lab description, therefore I don’t believe I observed all the appropriate reactivity reactions. The instructor was able to go over the propers reaction we should have seen with the halogens, while our own samples didn’t fully react, we saw a general idea of the reactivity of the Halogens. Iodine was found to be the least conductive halogen out of the three we sampled, and Chloride was found to be the highest. The metal reactivity happened very quickly and it know immediately known if the metal would react with one of the three liquids it was tested in. The metals were put through a series of three liquids: cold water, cold acid, then hot acid. For the metals that reacted in cold water, they were not tested for cold or hot acid. The metals that failed to react with cold water were then tested in cold acid. Metals that failed to react with cold acid where then placed in a warm water bath with the purpose to heat up the test tube containing the acid and metal. When the acid became warm enough, some metals showed a very vigorous reaction. The least reactive metal we found to be copper. Overall our most reactive metal was Sodium. Error Analysis: Our biggest source of error was adequately mixing the halogens within the test tube. The amount of mixing, or force to mix was not outlined in the lab manual and my partner and I failed to vigorously mix the halogens together. We saw an adequate reaction but not the full reactivity.

Post-Lab Questions: 1. Predict the reactivity of silicon in water relative to that of sodium, magnesium, and aluminum. Explain your answer. Water has little influence on silicon, due to a surface layer of silicon dioxide that is formed. Much like aluminum, which also has a surface layer, can only be observed when the layer is melted and washed away. 2. How does the reactivity of the halogens vary within its own group from top to bottom? The distance a valence electron is away from a positively charged nucleus means the halogen is less reactive. The closer the valence electrons are to the nucleus the more reactivity the halogens have. Evaluating group 17, the most reactive halogen is Fluorine, then Chlorine, Bromine, Iodine…This shows that our results of most to least reactive are accurate to the periodic table. 3. Define the Electronegativity. Electronegativity is a chemical property that describes the tendency of an atom to attract a shared pair of electrons towards itself. 4. When Cl2 is added to KI(aq), which element will undergo oxidation and which element with undergo reduction? Oxidized (Iodine) KI (aq) + Cl2 (aq) ⇾ KCl (aq) + I2 (s) Reduced (Chlorine)

Metal vs. Atomic Radius Covalent Atomic Radius (pm)

220 200 180 160 140 120 100 0

1

2

3

4

5

6

7

8

7

8

9

10

Metal

Metal vs. Ionic Radius 130 120

Iconic Radius (pm)

110 100 90 80

70 60 50 40 0

1

2

3

4

5 Metal

6

9

10

Metal vs Ionization Potential Ionization Potential (kJ/mol)

1000 900 800 700 600

500 400 0

1

2

3

4

5

6

7

8

9

10

8

9

10

Metal

Metal vs. Electronegativity 2.1

1.9

Electronegativity

1.7

1.5

1.3

1.1

0.9

0.7

0.5 0

1

2

3

4

5 Metals

6

7...