Date of Experiment ___ 10/6/13 _________
Date Report Submitted ____10/7/13___ __________
Title: Observation of Chemical Changes
Objectives: To observe some properties of chemical reactions.
To associate chemical properties with household products.
Have you made any changes to the procedure? No. Please Explain
Data Tables and Observation: Fill out the data sheet for the experiment and submit with this form.
Remember: Lab notes are evidence of your work and of your understanding of the concepts demonstrated in the experiments. They are also the primary basis for your chemistry lab grade. Create a neat document and try to express your thoughts clearly, concisely, and completely.
This lab can be found in the lab manual under “Observations of Chemical Changes.” It is absolutely essential that you read the discussion and review the sections of this lab (and all of the labs) BEFORE you begin the experiment and refer to it when you are working on this write up. Do not take the “short cut” and skim through or you will make errors that will affect your grade. The lab grade is worth 20% of your course grade and can make a difference in your final grade.
Your instructor is prepared to answer questions please use the discussion board so that your very good questions can be answered in a forum from which your fellow students may benefit.
Data Sheet for Experiment # 1 – Observations of Chemical Changes
Write down everything you observe, for example: color change (include the color before and after for each step), bubbles, solid formation (precipitate), etc. Indicate the difference, if any, observed on the dark paper versus the white paper. (9 pts)
Observation on White Paper
Observation on Dark Paper
NaHCO3 + HCl
Started clear, after adding HCl tiny bubbles.
HCl (an acid) + BTB
Started clear, transparent yellowish
Looks darker, almost orange
NH4OH (a base) + BTB
Started clear turned blue
HCl + blue dye
Started clear, turned green
NaOCl +blue dye
then add 1 drop of HCl
Started clear, turned blue and green
Could see some small bubbles.
NaOCl + KI
Then add 1 drop of starch
Clear to pale yellow, after adding starch turned black black Test at least 4 different food items for the presence of starch. + almond
Stayed the same
+ wheat bread
Stayed the same
+ hash brown
KI (potassium iodide) + Pb(NO3)2 lead nitrate)
Turned bright milky yellow
NaOH (base) + phenolphthalein
Started clear turned dark pink
HCl (acid) + phenolphthalein
Looks a little milky with tiny bubbles
NaOH + AgNO3
Started clear and turned a tan/brownish color
NH3 (ammonia) or NH4OH + AgNO3
Paper towel result
Stayed clear w/ bubbles, did not see any changes to the paper towel. same L
NH4OH and CuSO4
Turned light blue
Looks milky light blue
Before you clean up, answer question #4.
Answer to Question 4: (3 pts)
Describe the results of 3 household cleaning supplies (you may use non-commercial cleaning supplies as well) with the Acid –base Indicators: Bromothymol blue, and phenolphthalein
Conclusion: Acid or Base?
1 Mrs. Meyers counter-top cleaner
Turned green with a few bubbles base 1 Mrs. Meyers counter-top cleaner
Stayed clear base 2 Windex
Darker blue base 2 Windex
Turned pink at first then ended up being clear after a few minutes. base 3 Scrubbing Bubbles Bathroom Cleaner