SCH3U
Unit 1
Investigations/Activities
Developing an Activity Series
Pre-Lab



When observing a reaction occurring in a test tube, what tells you that a gas is being formed?
How would you compare the reaction in the test tubes to determine the one in which the
reaction is happening more rapidly?
What factors affect the reactivity of metals?
What is the WHMIS symbol commonly used for acids? Describe the precautions you would need
to take when working with acids?
Question
What is the order of reactivity of copper, iron, magnesium, and zinc in acid?
Experimental Design
Determine the amount of acid and metal needed to obtain an accurate response to the question.
Identify independent, dependent, and constant variables.
Analysis



What criteria did you use to determine the rate of a reaction?
List the metals in the order of the rate of reaction, from the fastest reaction to the slowest.
Research to find a use for metals that depends on their reactivity or lack of reactivity.
Analyzing Ionization Energy Data
Dry Lab
Complete the lab on pg 54, 55
Plot a graph and answer questions a, and b. Be as descriptive as possible.
Molecular Models
Activity
Using a Molecular Model Kit form the following compounds, and draw the Lewis structures:
 Hydrogen to hydrogen
 Oxygen to two hydrogen’s
 Nitrogen to three hydrogen’s
 Carbon to four chlorines
 Nitrogen to nitrogen
 Carbon to two oxygen’s
 Create 5 of your own structures
a. Which of the molecules required double or triple covalent bonds? Why?
b. Which of the molecules would you expect to be polar?
Lab Flame Test
A flame test is a procedure used to test qualitatively for the presence of certain metals in chemical compounds.
When the compound to be studied is excited by heating it in a flame, the metal ions will begin to emit light.
Based on the emission spectrum of the element, the compound will turn the flame a characteristic color. This
technique of using certain chemical compounds to color flames is widely used in pyrotechnics to produce the
range of colors seen in a firework display.
Certain metal ions will turn the flame very distinctive colors; these colors in turn can help identify the
presence of a particular metal in a compound. However, some colors are produced by several different
metals, making it hard to determine the exact ion or concentration of the ion in the compound. Some
colors are very weak and are easily overpowered by stronger colors. For instance, the presence of a
potassium ion in a compound will color a flame violet. But on the other hand, even trace amounts of
sodium ions in a compound produce a very strong yellow flame, often times making the potassium ion
very difficult to detect. To counteract the effects of any sodium impurities, one can view the flame
through a piece of cobalt blue glass. The cobalt glass absorbs the yellow light given off by sodium while
letting most other wavelengths of light pass through.
Question:
Will the charge of the metal or the bond to a halogen or nitrate change the ability to identify an
element? Does the colour change when a solution is prepared for the metal?
Materials:



Bunsen burner
Nichrome wire
Solutions (1.0 mol/L) of the following metal salts
o Barium chloride/nitrate
o
o
o
o
o
o
o
o
o
Calcium chloride/nitrate
Copper (I) chloride, copper (II) chloride, copper (II) nitrate
Iron (II) chloride, iron (III) chloride/nitrate
Lead (II) chloride/nitrate
Lithium chloride/nitrate
Potassium chloride/nitrate
Sodium chloride/nitrate
Strontium chloride/nitrate
2 unknown solutions
Experimental Design
Using the nichrome wire loop you will dip it into the powder or solutions to test for the colour, produced by
moving electrons within the atom. Between uses rinse the nichrome wire with distilled water and then dip into a
solution of hydrochloric acid; briefly heat in the flame and test another sample. Create a data table.
Analysis
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
List the colors observed in this lab from the highest energy to the lowest energy.
List the colors observed in this lab from the highest frequency to the lowest frequency.
List the colors observed in this lab from the shortest wavelength to the longest wavelength.
What is the relationship between energy, frequency, and wavelength?
Based on the results of your experiment, what metal was found in the unknown? Explain.
Do you think we can use the flame test to determine the identity of unknowns in a mixture?
Why or why not?
How are electrons “excited” in this experiment? What does it mean when the electrons are
“excited”?
Why do different chemicals emit different colors of light?
Why do you think the chemicals have to be heated in the flame first before the coloured light is
emitted?
Colourful light emissions are applicable to everyday life. Where else have you observed colourful
light emissions? Are these light emission applications related? Explain.
Symbol
Element
Color
As
Arsenic
Blue
B
Boron
Bright green
Ba
Barium
Pale/Yellowish Green
Ca
Calcium
Orange to red
Cs
Cesium
Blue
Cu(I
Copper(I)
Blue
Cu(II)
Copper(II) non-halide
Green
Cu(II)
Copper(II) halide
Blue-green
Fe
Iron
Gold
In
Indium
Blue
K
Potassium
Lilac to red
Li
Lithium
Magenta to carmine
Mg
Magnesium
Bright white
Mn(II)
Manganese(II)
Yellowish green
Mo
Molybdenum
Yellowish green
Na
Sodium
Intense yellow
P
Phosphorus
Pale bluish green
Pb
Lead
Blue
Rb
Rubidium
Red to purple-red
Sb
Antimony
Pale green
Se
Selenium
Azure blue
Sr
Strontium
Crimson
Te
Tellurium
Pale green
Tl
Thallium
Pure green
Zn
Zinc
Bluish green to whitish green