Ion Flame Test Inquiry - LABORATORY REPORT
NAME: Mrs. Perez
Lab Partners: …………………….
PURPOSE:
Focused Idea to Test / Testable Question / Hypothesis
To determine what part of a compound in household products is responsible for flame color in a flame test.
PREDICTION:
What do you think will happen in the experiment and why do you think that?
B.
Determining the Independent and Dependent variables:
1.
The Independent variable in this experiment is _____________________.
2.
The Dependent variable in this experiment is _____________________.
C.
Write a problem statement:
1.
How will the _______________________________________ (I.V.)
effect the ___________________________________________ (D.V.)?
PRE-LAB NOTES and RESEARCH:
Pre-lab questions and any research or background information referring to the content of the lab.
1. What is an ion?
2. Give an example of a cation and anion.
3. Give an example of an ionic compound.
4. What is a flame test?
MATERIALS:
What materials and equipment were used in this lab?
0.1 M Solutions of:
MgCl2 – Magnesium Chloride
CuCl2 – Copper Chloride
Matches
KCl – Potassium Chloride
Wooden Splints
CaI2 – Calcium Iodide
Propane Burner
BaCl2 – Barium Chloride
Sr(NO3)2 – Strontium Nitrate
NaCl – Sodium Chloride
PROCEDURES:
What steps were taken to complete this investigation?
1.
PUT ON YOUR GOGGLES AND KEEP THEM ON!!!
2.
Hold a wooden splint with tongs in the flame.
3.
Watch the flame color and observe any changes from the control.
4.
Repeat for all compounds at your station.
OBSERVATIONS AND DATA:
What did you observe during the lab? What data did you collect? (may include data tables)
Compound
Compound
Formula
Control ??
NaCl
BaCl2
Calcium
Iodide
Strontium
Nitrate
CuCl2
Positive
Ion
None
Negative
Ion
None
Cl-1
Flame
What ion
test color causes color?
None
Magnesium
Chloride
Unknown 1
Unknown 2
Unknown 3
Unknown 4
KCl
?
?
?
?
RESULTS / NARRATIVE OF FINDINGS:
Include any calculations such as averages, percent change, percent error and any graphs of data.
What did you observe during the flame tests?
DISCUSSION / INTERPRETATION OF RESULTS:
What do your results mean? How do they compare to your hypothesis? Answer any discussion or post-lab questions
here.
A.
Why is it important to test the flame color of the methanol without any compounds dissolved in it?
B.
Do the positive ions or the negative ions cause the change in flame color? Explain why based on your
observations.
C.
Why do ions have these characteristic flame colors?
D.
What can flame tests be used for?
E.
If milk that’s boiling spills over into the flame and burns, what color might the flame be? How do you know
that?
F.
If metallic salts produce different colors of light when burned, what is way that this is used in the world?
IMPLICATIONS FOR FUTURE STUDY:
What is something that you could research after this lab? What is another lab that could be an extension of this one?
RELEVANCE:
How does this lab relate to and help you understand the content from class?
Challenge questions:
A. Potassium gluconate (formula = K+C6H11O7-) produces a light purple flame. Copper
(II) sulfate (formula = Cu2+SO4-2) produces a green flame. What flame color would
you expect for copper (II) gluconate (formula = Cu2+[C6H11O7-]2)? Explain.
B.
How could you tell the following three white artificial sweetener powders apart using
the flame test? You have:
1. Equal (C14H18N2O5, a non-ionic compound)
2. Ace-K (K+C3H4NO4S-)
3. Sweet ‘N Low (Ca2+[C7H4NO3S-]2).
C.
Boric acid is a molecular, non-ionic compound. Based on its flame test there is a color
observed, but is this due to positive ions or negative ions? Why?