Download Spring Break Extra Credit Assignment

Name:_____________________________________________________ Hour:____________
Spring Break Extra Credit Assignment
Look up into the sky on a clear night. You may be able to see
about 3,000 stars with the naked eye, but the number of stars
swirling around you in the known universe is approximately
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equal to Avogadro’s number 6.02 x 10 . Just think, the known
universe contains approximately a mole of stars. You don’t
have to leave the Earth to encounter such a large number. The
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water in the Pacific Ocean has a volume about 6.02 x 10
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milliliters and a mass about 6.02 X 10 grams.
Avogadro’s number is almost incomprehensibly large. For example, if one mole of
dollars was given away at the rate of a million dollars per second beginning when
the Earth was first formed some 4.5 billion years ago, would any remain today?
Surprisingly, about three fourths of the original mole of dollars would be left
today; it would take about fourteen billion, five hundred million more years to
give away the remaining money at one million dollars per second.
The impressively large size of Avogadro’s number can give us very important
insights into the very small size of individual molecules. In a single drop of water
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there are about 1.7 x 10 water molecules. There are more teaspoons of water in
the Atlantic Ocean than there are water molecules in a teaspoon of water.
Purpose: During the activity comparisons will be made to facilitate your
comprehension of both the magnitude of Avogadro’s number and the size of
molecules, atoms and ions. Data will be collected and used as conversion factors
to solve problems using dimensional analysis.
Since you may not (probably don’t) have all of these materials at home, you can
use the values in bold to perform your calculations.
Procedure:
1. Determine the number of seconds it takes to count 100 rice grains using a stop
watch. (95 seconds to count 100 grains of rice)
2. Determine the length of 20 rice grains laid end to end in cm. (12.5 cm per 20
grains of rice)
3. Determine the space filled volume of 100 rice grains using a 10 ml graduated
cylinder. (2.5 mL per 100 grains of rice)
4. Determine the mass of 100 rice grains. (1.600 g per 100 grains of rice)
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Conclusion:
1. Calculate the number of years would it take for you to count one mole of rice
grains?
2. Calculate the number of years it would take the population of the Earth to
count Avogadro’s number of rice grains?
3. Determine how many rice grains laid end to end it would take to reach the sun?
4. How deep, in miles, would the state of Michigan be covered if one mole of rice
grains were poured on top of Michigan?
5. Would a mole of rice grains laid end to end come closer to the sun or the
nearest star?
6. Assuming that the nearest star is 4.3 light years away from the earth, how
many rice grains laid end to end would it take to reach the nearest galaxy?
7. The annual production of rice is 32,000,000,000,000 Kg. How many years
would it take to grow a mole of rice grains?
8. Assuming that man has grown rice for 200,000 years, has there been a mole of
rice grown yet on Earth?
USEFUL FACTS AND FIGURES AND IRRELEVANT TID BITS
One light year is 5,865,676,000,000 miles
2.54 cm is an inch
5280 feet are in a mile
A football field is 98.97 meters long
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Michigan has a surface area of 96,716 miles
It is 93 million miles to the sun on a clear day at noon
Earth’s population is about 6 billion
MOLE FACT
If a mole of pennies were divided up and given to every person on the earth, each
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person would receive 1.5 X 10 pennies. Personal spending at a rate of one
million dollars a day would use up each person’s wealth in just over four thousand
years. Life would be comfortable; however, the surface of the earth would be
covered in copper coins to a depth of 420 meters.
*Original Activity taken from Rhonda Alexander Robert E. Lee High School Tyler, TX
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Name:_____________________________________________________ Hour:____________
Spring Break Extra Credit Answer Sheet
Conclusion:
1. Calculate the number of years would it take for you to count one mole of rice
grains?
2. Calculate the number of years it would take the population of the Earth to
count Avogadro’s number of rice grains?
3. Determine how many rice grains laid end to end it would take to reach the sun?
4. How deep, in miles, would the state of Michigan be covered if one mole of rice
grains were poured on top of Michigan?
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5. Would a mole of rice grains laid end to end come closer to the sun or the
nearest star?
6. Assuming that the nearest star is 4.3 light years away from the earth, how
many rice grains laid end to end would it take to reach the nearest galaxy?
7. The annual production of rice is 32,000,000,000,000 Kg. How many years would
it take to grow one mole of rice grains?
8. Assuming that man has grown rice for 200,000 years, has there been a mole of
rice grown yet on Earth?
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