Lab: Plop Plop Fizz Fizz Reaction Rate
Name
Period
Date
Team Names
Background: Alka Seltzer and other effervescent antacid pain reliever tablets are made using solid forms of aspirin,
citric acid, and sodium bicarbonate. When sodium bicarbonate dissolves in water, it dissociates (splits apart) into
sodium (Na+) and bicarbonate (HCO3−) ions. The bicarbonate then reacts with hydrogen ions (H+) from the citric
acid to form carbon dioxide and water. It will be your task to predict conditions that will change the rate at which
this reaction happens and then create lab conditions to test your hypotheses.
Materials:
Small beaker (250 – 400 ml)
Timer (clock or watch with second hand)
Effervescent tablets
Graduated cylinder (100 ml)
Mortar and pestle
Hot or cold tap water
Thermometer
Baseline Reaction:
1.
2.
3.
4.
5.
Using the graduated cylinder, measure out 50 ml of tap water and transfer it to the beaker.
Measure the temperature of the water in the beaker and record it here:
Prepare to measure how long it takes the tablet to completely react.
(Reaction starts when tablet is dropped and continues until tablet is gone and the fizzing noise has stopped.)
Drop a tablet into the beaker and measure the reaction time to the nearest second.
Record the seconds for the reaction here: BASELINE REACTION TIME
(seconds)
Factors: We studied 5 factors that typically effect reaction rate. Record them here:
2)
3)
4)
1)
5)
Experimental Design:
1. Utilizing the materials provided, design individual experiments for as many of these
factors as you can to see what impact each of them has on the reaction rate.
2.
Remember to keep in mind that a Controlled Experiment needs to have most things held constant while one
variable is manipulated at a time. Be sure to think about which variables (things that could change) need to
be held constant in order to do this in a controlled fashion.
3. You are limited to one tablet per experiment, and no more than 100 ml of water for any given experiment.
4. Your team will be allowed to run up to 4 individual experiments (in addition to baseline reaction).
5. Design for each experiment will be approved by instructor before you get a tablet to run the experiment.
(Be sure to record the temperature as part of conditions for each experiment.)
Exp Reaction
Detailed Description of Conditions
Prediction*
Reaction Time
% of Baseline
(Exp secs/Base secs)
(faster or slower)
(# seconds)
(exactly record all reaction factors each time)
Factor
#1
#2
#3
#4
#5
* Prediction is faster or slower compared to Baseline experiment reaction time
WRITE UP CONCLUSIONS ON BACK OF PAGE
Conclusions:
1. Create a bar chart for your data. Include results for the baseline and all the
experiments. Be sure to include a title for the chart and to clearly label all data and to
label both axis.
Reflections:
2. If any of your predictions were incorrect, try to you think of a reason(s) why
and describe it below. Also, how you could improve your data with another
experiment(s)?
Lab: Plop Plop Fizz Fizz Reaction Rate – Write Up RUBRIC
Author Name
Evaluator Name
Title Page
Possible: 2
Introduction: Discussion of reaction rate factors
Possible: 10
Materials List
Possible: 3
Experimental Design: Procedures for each experiment
Possible: 25 ______
Baseline reaction: Water temp & reaction time – 1 pt each
Possible: 2
Reaction rate factors – 1 pt each
Possible: 5
Experimental data (up to sets) – Conditions 3 pts/1 each for rest
Possible: 28
Bar Chart:
Title, Axis labels, and accurate scale – 5 pts
Possible: 5
Data: each factor correctly plotted, clearly labeled – 5 pts
Possible: 25
Conclusion/Reflections: 20 pts
Possible: 20
(Possible: 125)
Comments:
Total
______
______
Lab: Plop Plop Fizz Fizz Reaction Rate – Write Up RUBRIC
Introduction:
Should discuss the 5 factors which affect reaction rates - providing background on how
each factor specifically relate to reaction rate. Also discuss the background for the baseline
experiment and present the purpose of this lab. (hint – observe how reaction rate is affected)
Materials:
List all materials used in the experiments
Procedures:
Outline step by step the procedures followed for each individual experiment including
the baseline experiment. Provide a sub-heading for each individual experiment within the
section heading.
Example – Procedures:
Baseline Experiment:
1. ………
Data:
Present all data collected in a chart like the one listed on the data sheet. This chart should
be inserted into the write-up in the appropriate order – Do not simply reference of attach the data
sheet! Do not forget to list the data from the baseline experiment – either add in a section to the
data chart, create a separate chart, or simply list and label the baseline data (before the data
chart).
The Bar Graph/Chart should also be presented within the paper. Either create the chart
using the computer or insert the graph paper model into the flow of the paper and then manually
create the graph.
Conclusion:
Write a conclusion passed on your reflections. The conclusion should address the results
of each experiment, and discuss them in relation to the facts presented in the introduction. The
conclusion should bring the report full circle – tying everything up – bringing it all together back
to the introduction discussion.
Other Important Notes:
 Use headings for each section – just like they are listed on this sheet – keep in order.
 You will not be turning in the lab data sheet – all data and information will be presented
in the write – up.
 DO NOT use first or second person – NO: I’s, WE’s, YOU’s, etc. – everything should be
addressed in third person.
 Use good writing – transitions & conclusion sentences.
o Be concise and specific – this is not about quantity but about quality! However
cover everything in detail!
o Use the lab instructions and data sheet to help you! It lays out a lot of information
and order for you.
 If you have any questions please ask! Do not wait for the last minute to complete this –
Worth a test grade!
Lab: Plop Plop Fizz Fizz Reaction Rate
Name
KEY
Period
Date
Team Names
Background: Alka Seltzer and other effervescent antacid pain reliever tablets are made using solid forms of aspirin,
citric acid, and sodium bicarbonate. When sodium bicarbonate dissolves in water, it dissociates (splits apart) into
sodium (Na+) and bicarbonate (HCO3−) ions. The bicarbonate then reacts with hydrogen ions (H+) from the citric
acid to form carbon dioxide and water. It will be your task to predict conditions that will change the rate at which
this reaction happens and then create lab conditions to test your hypotheses.
Materials:
Graduated cylinder (100 ml)
Mortar and pestle
Hot or cold tap water
Thermometer
Small beaker (250 – 400 ml)
Timer (clock or watch with second hand)
Effervescent tablets
Baseline Reaction:
1.
2.
3.
4.
5.
Using the graduated cylinder, measure out 50 ml of tap water and transfer it to the beaker.
Measure the temperature of the water in the beaker and record it here:
XX F or XX C
Prepare to measure how long it takes the tablet to completely react.
(Reaction starts when tablet is dropped and continues until tablet is gone and the fizzing noise has stopped.)
Drop a tablet into the beaker and measure the reaction time to the nearest second.
Record the seconds for the reaction here: BASELINE REACTION TIME
XX (seconds)
Factors: We studied 5 factors that typically effect reaction rate. Record them here:
2)Surface Area
3)Mixing
4)Concentration
1)Temperature
5)Catalyst
Experimental Design:
1. Utilizing the materials provided, design individual experiments for as many of these
factors as you can to see what impact each of them has on the reaction rate.
2.
Remember to keep in mind that a Controlled Experiment needs to have most things held constant while one
variable is manipulated at a time. Be sure to think about which variables (things that could change) need to
be held constant in order to do this in a controlled fashion.
3. You are limited to one tablet per experiment, and no more than 100 ml of water for any given experiment.
4. Your team will be allowed to run up to 4 individual experiments (in addition to baseline reaction).
5. Design for each experiment will be approved by instructor before you get a tablet to run the experiment.
(Be sure to record the temperature as part of conditions for each experiment.)
Exp Reaction
Detailed Description of Conditions
Prediction*
Reaction Time
% of Baseline
(Exp secs/Base secs)
(faster or slower)
(# seconds)
(exactly record all reaction factors each time)
Factor
#1
factor
XX mls XX temp other
faster
XX sec
XXX %
#2
#3
#4
#5
* Prediction is faster or slower compared to Baseline experiment reaction time
WRITE UP CONCLUSIONS ON BACK OF PAGE
Conclusions:
1. Create a bar chart for your data. Include results for the baseline and all the
experiments. Be sure to include a title for the chart and to clearly label all data and to
label both axis.
Reflections:
2. If any of your predictions were incorrect, try to you think of a reason(s) why
and describe it below. Also, how you could improve your data with another
experiment(s)?
Lab was developed by Scott Grigg in Feb, 2010. Background for this lab:
The main ingredients of Alka-Seltzer tablets are aspirin, citric acid, and sodium bicarbonate (NaHCO3).
When sodium bicarbonate dissolves in water, it dissociates (splits apart) into sodium (Na+) and
bicarbonate (HCO3−) ions. The bicarbonate reacts with hydrogen ions (H+) from the citric acid to form
carbon dioxide and water. The reaction is described by the following chemical equation:
Sodium Bicarbonate
NaHCO3 ( Na+ + HCO3−
Citric acid (C6H8O7) is a weak organic acid with 3 carboxyl groups:
HYPERLINK "http://upload.wikimedia.org/wikipedia/commons/c/c5/Zitronens%C3%A4ure__Citric_acid.svg" INCLUDEPICTURE
"http://upload.wikimedia.org/wikipedia/commons/thumb/c/c5/Zitronens%C3%A4ure__Citric_acid.svg/256px-Zitronens%C3%A4ure_-_Citric_acid.svg.png" \* MERGEFORMATINET
H+ + HCO3− ( H2O + CO2
Citric acid
From Wikipedia, the free encyclopedia
Not to be confused with
C" Vitamin C .
HYPERLINK "http://en.wikipedia.org/wiki/Vitamin_C" \o "Vitamin
Citric acid is a weak HYPERLINK "http://en.wikipedia.org/wiki/Organic_chemistry" \o
"Organic chemistry" organic
HYPERLINK "http://en.wikipedia.org/wiki/Acid" \o "Acid"
acid , and it is a natural HYPERLINK "http://en.wikipedia.org/wiki/Preservative" \o
"Preservative" preservative and is also used to add an acidic, or HYPERLINK
"http://en.wikipedia.org/wiki/Taste" \l "Sourness" \o "Taste" sour , taste to foods and
HYPERLINK "http://en.wikipedia.org/wiki/Soft_drink" \o "Soft drink" soft drinks . In
HYPERLINK "http://en.wikipedia.org/wiki/Biochemistry" \o "Biochemistry" biochemistry ,
it is important as an intermediate in the HYPERLINK
"http://en.wikipedia.org/wiki/Citric_acid_cycle" \o "Citric acid cycle" citric acid cycle and
therefore occurs in the HYPERLINK "http://en.wikipedia.org/wiki/Metabolism" \o
"Metabolism" metabolism of virtually all HYPERLINK
"http://en.wikipedia.org/wiki/Life" \o "Life" living things . It can also be used as an
environmentally benign cleaning agent.
Citric acid exists in greater than trace amounts in a variety of HYPERLINK
"http://en.wikipedia.org/wiki/Fruit" \o "Fruit" fruits and vegetables, most notably
HYPERLINK "http://en.wikipedia.org/wiki/Citrus_fruit" \o "Citrus fruit" citrus fruits .
HYPERLINK "http://en.wikipedia.org/wiki/Lemon" \o "Lemon" Lemons and
HYPERLINK "http://en.wikipedia.org/wiki/Lime_(fruit)" \o "Lime (fruit)" limes have
particularly high concentrations of the acid; it can constitute as much as 8% of the dry weight of
these fruits (about 47 HYPERLINK "http://en.wikipedia.org/wiki/Gram_per_litre" \o "Gram
per litre" g/L in the juices HYPERLINK "http://en.wikipedia.org/wiki/Citric_acid" \l "cite_note-2#cite_note-2" [3] ).
The concentrations of citric acid in citrus fruits range from 0.005 HYPERLINK
"http://en.wikipedia.org/wiki/Molarity" \o "Molarity" mol/L for oranges and grapefruits to
0.30 mol/L in lemons and limes. Within species these values vary depending on the
HYPERLINK "http://en.wikipedia.org/wiki/Cultivar" \o "Cultivar" cultivar and the
circumstances in which the fruit was grown. At room temperature, citric acid is a white
crystalline powder. It can exist either in an HYPERLINK
"http://en.wikipedia.org/wiki/Anhydrous" \o "Anhydrous" anhydrous (water-free) form or as
a HYPERLINK "http://en.wikipedia.org/wiki/Hydrate" \o "Hydrate" monohydrate . The
anhydrous form crystallizes from hot water, where as the monohydrate forms when citric acid is
crystallized from cold water. The monohydrate can be converted to the anhydrous form by
heating above 78 °C. Citric acid also dissolves in absolute (anhydrous) ethanol (76 parts of citric
acid per 100 parts of ethanol) at 15 degrees Celsius.
In chemical structure, citric acid shares the properties of other HYPERLINK
"http://en.wikipedia.org/wiki/Carboxylic_acid" \o "Carboxylic acid" carboxylic acids . When
heated above 175°C, it decomposes through the loss of HYPERLINK
"http://en.wikipedia.org/wiki/Carbon_dioxide" \o "Carbon dioxide" carbon dioxide and
HYPERLINK "http://en.wikipedia.org/wiki/Water_(molecule)" \o "Water (molecule)"
Citric acid leaves a white crystalline precipitate.
water .
Citric acid is a slightly stronger acid than typical carboxylic acids because the anion can be
stabilized by intramolecular hydrogen-bonding from other protic groups on citric acid