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Part 3. reactions of metals with other metal ions 

  • Place a clean 1 inch-square of metal foil (sheet) of each of these metals Cu, Zn and Pb on a flat surface.
  • Clean the metal surfaces by sanding them with fine sandpaper or steel wool.
  • Place one or two drops in spots of each of these solutions in a clockwise order on the metal surfaces:
A. 0.5 M Ag + size 12{"Ag" rSup { size 8{+{}} } } {}
B. 0.5 M Cu 2 + size 12{"Cu" rSup { size 8{2+{}} } } {}
C. 0.5 M Zn 2 + size 12{"Zn" rSup { size 8{2+{}} } } {}
D. 0.5 M Pb 2 + size 12{"Pb" rSup { size 8{2+{}} } } {}
  •  NOTE: Do not test a cation of a metal on a square of the same metal such as Cu 2 + size 12{"Cu" rSup { size 8{2+{}} } } {} ion and Cu metal.
  • Watch for color changes in each spot as evidence of reaction. If you are not sure whether the reaction has occurred, rinse the plate with water. A distinct spot of a different color on the surface is good evidence for the reaction.
  • Write net ionic equations for each reaction . Arrange Ag, Cu, Pb and Zn in order of their increasing strength as reducing agents. If a metal A reacts with a cation of another metal B, metal A is a stronger reducing agent, more reactive than metal B.
  • Rinse and dry each square of metal and return it to the correct beaker on the reagent shelf for other students to use.

Part 4. flame tests

One station set up that all sections will rotate through

Clean a spatula wire by dipping it into dilute hydrochloric acid (3M) and then holding it in a hot Bunsen flame. Repeat this until the spatula doesn't produce any color in the flame.

When the spatula is clean, moisten it again with some of the acid and then dip it into a small amount of the solid you are testing so that some sticks to the spatula. Place the spatula back in the flame again.

If the flame color is weak, it is often worthwhile to dip the spatula back in the acid again and put it back into the flame as if you were cleaning it. You often get a very short but intense flash of color by doing that.

Chemicals/Materials:

  • Chloride salts of Li, Na, K, Rb, Cs, Ca, Ba, Cu, Pb, Fe (II) and Fe(III) Sr (nitrate salt).
  • Glass rods with loops of Pt wire.
  • Bunsen burner/clicker.
  • Concentrated nitric acid or hydrochloric acid.

Record your observations on your report form.

It should be noted that sodium is present as an impurity in many if not most metal salts. Because sodium imparts an especially intense color to a flame, flashes of the sodium may be observed in nearly all solutions tested.

Pre-lab 5: the best table in the world!

Hopefully here for the Pre-Lab

Name(Print then sign): __________________________________________________

Lab Day: ___________________Section: ________TA________________________

This assignment must be completed individually and turned in to your TA at the beginning of lab. You will not be allowed to begin the lab until you have completed this assignment.

  • The mass of an atom of the element in atomic mass units (amu) for the molar mass of a mole ( 6 . 02 × 10 23 size 12{6 "." "02" times "10" rSup { size 8{"23"} } } {} ) of atoms in grams above or below the chemical symbol for each element? Circle the correct one.
  • The second symbol listed for each element is the _______ __________, symbol ________? Fill in the blanks.
  • The number in question 2 gives the number of
    • ____________ or
    • the number of ________________ for a neutral atom. Fill in the blanks
  • The elements in a given vertical column are referred to as a _________ or __________. Fill in the blanks.
  • The horizontal rows are called __________? Fill in the blank
  • The block of elements between groups II and III are called ___________ _________? Fill in the blanks.
  • Elements 58 to 71 are known as ____________ or __________________? Fill in the blanks.
  • Elements 90 to 103 are known as _________ ____________? Fill in the blanks.
  • Do elements with larger atomic numbers than 92 occur naturally? True or false? Circle the correct one.

Report 5: the best table in the world!

Hopefully here for the Report Form

Note: In preparing this report you are free to use references and consult with others. However, you may not copy from other students’work (including your laboratory partner) or misrepresent your own data (see honor code).

Name(Print then sign): __________________________________________________

Lab Day: ___________________Section: ________TA________________________

I. activity series

Part 1. reactions of metals with water

Metal Observations Net Ionic Equations (If NoReaction Occurs, write N.R)
Na
K
Mg
Cu
Zn
Ca

Part 2. reactions with hcl

Metal Observations Net Ionic Equations (If No Reaction Occurs, Write N.R.)
Mg
Cu
Zn

2. Based on your experimental results place Mg, Cu, Zn and Ca in order of increasing strength as reducing agents.

Part 3. reactions with other metal ions

1. Write in the appropriate box either“REACTION”or“NO REACTION”.

Zn Cu Pb
Ag + size 12{"Ag" rSup { size 8{+{}} } } {}
Cu 2 + size 12{"Cu" rSup { size 8{2+{}} } } {} Do not test
Zn 2 + size 12{"Zn" rSup { size 8{2+{}} } } {} Do not test
Pb 2 + size 12{"Pb" rSup { size 8{2+{}} } } {} Do not test

2. Write balanced equations to represent the results tabulated above.

3. Based on your experimental results, arrange Ag, Cu, Zn and Pb in order of increasing strength as reducing agents.

4. Arrange Ag + size 12{"Ag" rSup { size 8{+{}} } } {} , Cu 2 + size 12{"Cu" rSup { size 8{2+{}} } } {} , Zn 2 + size 12{"Zn" rSup { size 8{2+{}} } } {} and Pb 2 + size 12{"Pb" rSup { size 8{2+{}} } } {} in order of increasing strength as oxidizing agents.

5. Combine the results from Part 2 and Part 3. Arrange Mg, Cu, Zn, Ca, Ag and Pb in order or increasing strength as reducing agents.

6. Place Ni in this row, if it is found that Ni will deposit on Zn foil, but not on Pb foil when a drop of NiSO 4 size 12{"NiSO" rSub { size 8{4} } } {} is placed on both.

Part 4. flame tests

Element Color in flame
Li
Na
K
Rb
Cs
Ca
Sr
Ba
Cu
Pb

What are the limitations of this test?

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Source:  OpenStax, Honors chemistry lab fall. OpenStax CNX. Nov 15, 2007 Download for free at http://cnx.org/content/col10456/1.16
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