FRIDAY, SEPTEMBER 4TH, 2015DON’T TOUCH LAB EQUIPMENT

TILL TOLD.

I-CAN: OBSERVE PHYSICAL CHANGES IN A GUMBALL.

DO NOW: PUT EVERYTHING ON THE BACK COUNTER EXCEPT FOR A PENCIL.

TOC: GUM BALL LAB – PG. 26&27.

WHAT IS THE MASS SHOWING?

Click here for an online interactive triple-beam balance!

BUBBLE GUM!

LAB WRITE UPBubble Gum Lab

What happens to the mass of gum after chewing for 10 minutes?

• Mass = The amount of matter an object has.• the weight of an object includes the force of gravity on

that object (If we traveled to the moon, we would have the same mass but we would weigh less on the moon than here on Earth because there is less gravity).

• For our lab, we will measure mass by the weight of the object in grams (g)

TRIPLE-BEAM BALANCEWe often use a triple-beam balance to measure mass.

With the pan empty, move the three sliders on the three beams to

their leftmost positions, so that the balance reads zero.

If the indicator on the far right is not aligned with the fixed mark, then calibrate the balance by turning the set screw on the left under the pan.

Once the balance has been calibrated, place the object to be measured on the pan.

Move the 100 gram slider along the beam to the right until the indicator drops below the fixed mark. The notched position immediately to the left of this point indicates the number of hundreds of grams.

Now move the 10 gram slider along the beam to the right until the indicator drops below the fixed mark. The notched position immediately to the left of this point indicates the number of tens of grams.

The beam in front is not notched; the slider can move anywhere along the beam. The boldface numbers on this beam are grams and the tick marks between the boldface numbers indicate tenths of grams.

To find the mass of the object on the pan, simple add the numbers from the three beams.

As with a ruler, it is possible to read the front scale to the nearest half tick mark.

THE SCIENTIFIC INQUIRY METHOD1.Lab Title – top left hand corner of large paper

2.Problem (question)

3.Hypothesis (what you think will happen, based on experience and research If… then…)

4.Materials (shopping list)

5.Procedure (number each step)

6.Data (data table or chart and written observations and pictures)

7.Results – graph your data

8.Conclusion

• Explain how your hypothesis was supported/not supported by the data from your experiment

• Identify any possible errors or factors that could have affected your experiment

• Discuss what you might do differently next time, what other related experiments you would want to do, what you would do differently next time

RESEARCH QUESTIONS VS. TESTABLE QUESTIONS.Research questions: can be answered by looking them up.

• How many calories are in a stick of gum?• How much fat is in a stick of gum?• What is the most expensive gum?

Testable questions: can be answered by performing an experiment

• Which flavor of gum will weigh the least or most after being chewed?

• Which brand of gum makes the biggest bubbles?

HYPOTHESISDefinition - what you think will happen & why.

Write in the “If… then…because…” format

If I chew gum for 10 minutes, then the mass will

• Stay the same because…• Increase because…• Decrease because…

MATERIALS

1. Triple Beam Balance

2. 6 different flavors of bubble gum

3. Timer

4. Aluminium paper

PROCEDURE1. Weigh the gum

• Place the un-chewed gum on the triple beam balance• Find and record the weight in grams (g)

2. Chew the gum for 10 minutes

• No talking

3. Weigh the gum again

• Place the chewed gum back on the triple beam balance• Find and record the weight in grams (g)

DATA

Mass of gum before chewing: ______gMass of gum after chewing: _______g

DATA CHART FOR CLASS

GRAPH THE DATA

Rainb

lo

Hubba

Bub

ba

Bubba

licio

us

Bazoo

ka

Doubl

e Bub

ble

Orbit W

hite

SF

0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

By Golly By Gum

Total Mass

Chewed Mass

Brands of Gum

Ma

ss

in g

ram

s

CONCLUSION1. Explain how your hypothesis was supported/not

supported by the data from your experiment

• My hypothesis was not supported. I predicted the mass of the gum would increase (or stay the same) but the mass of the gum decreased. The mass of the gum went from ___g to ___g. or

• My hypothesis was supported. I predicted the mass of the gum would decrease and it did decrease. The mass of the gum went from ___g to ___g

2. Identify any possible errors or factors that could have affected your experiment

3. Discuss what you might do differently next time, what other related experiments you would want to do, what you would do differently next time