Lab

Ms. Pezzi

Chemistry Hr. 1, 2, 3, 8

09/09/09

Sample Lab Report

Making Root Beer Floats

Purpose

In this lab, we are trying to determine if changing the type of root beer has an effect on the texture of ice cream in a root beer float. In addition, we are using this lab as a fun way to end the first week of chemistry and to learn how to write a lab report.

Materials

A&W ® Root Beer

A&W ® Diet Root Beer

Kemps ® Vanilla Ice Cream

Equipment

ice cream scoop

3 oz Dixie ® cup

plastic teaspoon

Safety and Disposal

Material / Safety - Common Knowledge / Disposal
Root Beer / contents are under pressure; use caution and point bottle away from others when opening / pour down drain
Ice Cream / very cold; may cause unpleasant sensations to some peoples’ teeth / place in sink; run water to melt ice cream and to wash down drain
Root Beer Float / may be very cold; sugar may cause hyperactivity; sticky mess may result from spill / if not completely eaten, pour it into a sink in the lab area and rinse it down the drain

Procedure

1.  With the ice cream scoop, scoop out enough ice cream to loosely fill about ½ of one small cup. Fill the second cup with the same amount of ice cream. Record the number of scoops you used.

2.  Pour regular root beer into one cup and the same amount of diet root beer into your other cup. Estimate and record the amount of root beer you used.

3.  Wait about 2 minutes before you taste your floats. While waiting, record observations.

4.  After waiting, taste each of the floats. Use the plastic spoon if necessary. Record observations.

5.  Clean up area and properly dispose of materials. Throw cups into garbage can. Rinse spoons and place in dishpan.

Observations

Before Mixing / Making Float / Tasting Float
Regular Root Beer / brown liquid
fizzy
root beer odor
cold / soda light brown in color
opaque
less fizzy
Diet Root Beer / brown liquid
fizzy
root beer odor
cold / soda light brown in color
big bubbles on top of cup
lots of fizz
Ice Cream / cream colored solid
stuck to ice cream scoop
very cold / color turned tannish
Regular Float / soda foamed up when added to ice cream
ice cream floated / very sugary; heavy tasting
smooth
cold
ice cream blends into soda
float lighter brown/tan color
tan residue remains
Diet Float / soda foamed and overflowed cup when added to ice cream
ice cream stuck to sides of cup / lighter tasting – not sugary
ice cream crunchy
float lighter brown/tan color
brown/tan ice crystals remained on ice cream after soda poured out

Data

Ice Cream Amount (scoops) / Root Beer Amount (Dixie ® cups)
Regular Float / 0.33 / 0.75
Diet Float / 0.5 / 0.5

Graph

Not required for this lab.

Calculations

1.  Regular Float

3 oz = x oz

1 cup 0.75 cup

x = 2.25 oz

29.6 mL = x mL

1 oz 2.25 oz

x = 66.6 mL

Diet Float

3 oz = x oz

1 cup 0.5 cup

x = 1.5 oz

29.6 mL = x mL

1 oz 1.5 oz

x = 44.4 mL

Questions

1.  Three similarities between the root beer floats were the foaminess of the root beer after being added to the cups, the coldness of the floats, and the color of the floats.

2.  Three differences between the root beer floats were the taste, texture, and remaining residue when the floats were dumped out.

Analysis

In this lab, we were trying to determine if changing the type of root beer from regular to diet would affect the texture of the ice cream in a root beer float. To do this lab, we worked in pairs and each partner made a root beer float We tried to keep the amounts of root beer and ice cream the same, but since we didn’t scoop out the ice cream at the same time, we ended up with different amounts (0.33 scoops for me and 0.5 scoops for my partner). Because we had different amounts of ice cream, we had to use different amounts of soda.

The results of the lab showed us that the root beer floats were different when different kinds of soda is used. This supported our hypothesis which was that if we changed the type of root beer from regular to diet, then the texture of the ice cream would be different. Our evidence for this is that the texture of the regular root beer float was smooth, while the texture of the diet root beer float was crunchy.

Because a change in the soda led to a change in the texture of the float, there must be something about regular and diet root beer that causes this. Our group thinks that the reason the floats were different is related to the amount of fizziness in the two sodas. When the regular soda was added to the ice cream, the soda foamed, but when the diet was added, the soda foamed so much that it overflowed the cup.

Our experimental design was not perfect in this lab. To be considered a better experiment, we would have to use the same amount of ice cream and soda in the two floats. To ensure that we used the same amounts, we would measure the mass of the ice cream on a balance and the volume of root beer in a graduated cylinder. We would also time the floats to make sure we were letting them sit for the same amount of time. In addition, we would repeat the trials several times with the same amounts to make sure our data were reproducible.

Visual Aid

See attached sheet

Personal Evaluation

My role in this lab was to make the regular root beer float and to write an individual lab report. I really enjoyed the lab and hope that we can do more labs like this. I exerted a little effort in making the float because it wasn’t too hard, but I exerted a lot of effort in my lab report. I learned that chemistry is everywhere – even root beer and ice cream are made of chemicals. Two questions I have about this lab are:

1.  Would the floats be different if we used regular root beer and regular Mt. Dew?

2.  Is the amount of carbonation in regular and diet root beer the same or different?