Bell Ringer

Bell Ringer
How does surface area affect a
chemical reaction?
Today’s Goal
I can apply my knowledge of
chemical reaction to the real world
experience of making fudge.
 I can identify endothermic and
exothermic reactions in real world
• 3 cups sugar
• 1 ½ sticks of country crock butter
• 2/3 cup of cream
• 1 (7 oz.) jar of marshmallow crème
• 1 (12 oz. package) of __________
• Energy
Recall that activation energy is
minimum amount of energy needed
to start a reaction.
 The energy for today’s experiment
will come from the hot plate.
 1. Explain how the energy gets from the
electrical outlet to the pan to heat the
In a pan
 Mix the first 3 ingredients (reactants)
until they dissolve into one
 This will happen as the heat goes
into the pan (endothermic)
Once they mix together to form a
compound OBSERVE the color of the
 Record a description of your
At this point we observe for the
mixture to begin to boil. The mixture
must absorb enough energy to come
to a rolling boil. (It cannot be stirred
down) OBSERVE Record observation.
 Now we begin to time. Time for 6
min. Then we will look at the color of
the compound.
Time’s UP
 We remove the compound from the
 Add the (inhibitor) chips, and
marshmallow crème.
 Mix thoroughly and immediately pour
in the pan.
This is where the exothermic part of
the reaction is taking place.
 Feel the heat being released.
 Let the majority of the heat be
released. When the fudge is cool we
can eat it.
 While you are waiting!
Write up this experiment.
 Analysis
• Explain in detail how making fudge is
indeed a chemical reaction.
• Use the vocabulary words. (page 514)
or your homework (the vocabulary
• The analysis must use science
vocabulary correctly.
• Terms to include: endothermic,
exothermic, reaction rate factors,
reactants, products, evidence of a
chemical change
• Be specific! Begin now while you wait to
eat your experiment.
• Analysis is due tomorrow. You may use your
notes, book, etc…