ST-ST-ST-STOICHIOMETRY!!!! / Moles, Atoms, Molecules, Molar Mass
Determine the molar masses of the following chemical substances. Write correct units!
1) Cl2
2) KOH
3) BeCl2
4) FeCl
5) BF3
6) CCl2F2
Complete the following conversions using TRAIN TRACKS. Think about which conversion factors to use!
Moles à Atoms/Molecules
7) How many atoms are in 2.4 moles of a metal coin?
8) How many molecules are in 13.6 moles of oxygen gas?
9) How many moles are in 7.98 x 1024 atoms of a cold drink?
10) How many moles are in 1.3 x 1023 molecules of cerium oxide?
Moles à Mass
11) How many moles are in 34 grams of LiOH?
12) How many grams are there in 3.4 x 1024moles of NH3?
13) What is the mass of 4.2 moles of Ca(NO3)2?
14) How many moles are in 17 grams of CH4?
One Mole is A Lot of Things
When working with the mole concept, students often have trouble comprehending the enormous size of Avogadro's number, 6.02 x 1023. The following analogies may be helpful for students.
· If there were a mole of rice grains, all the land area in the whole world would be covered with rice to a depth of about 75 meters.
· One mole of rice grains is more grains than all the grain that has been grown since the beginning of time.
· One mole of rice would occupy a cube about 120 miles on an edge!
· Computers can count at the rate of over 800 million counts per second. At this rate it would take a computer over 25 million years to count to 6.02 x 1023.
· A mole of marshmallows would cover the United States to a depth of 600 miles
· In order to put a mole of rain drops in a 30 meter (about 100 feet) diameter tank, the sides of the tank would have to be 280 times the distance from the Earth to the Sun.
· A mole of hockey pucks would be equal to the mass of the Moon.
· Assuming that each human being has 60 trillion body cells (6.0 x 1013) and the Earth's population is 6 billion (6 x 109), the total number of living human body cells on the Earth at the present time is 3.6 x 1023or a little over half of a mole.
· If one mole of pennies were divided up among the Earth's population, each person would receive 1 x 1014 pennies. Personal spending at the rate of one million dollars a day would use up each persons wealth in about three thousand years. Life would not be comfortable because the surface of the Earth would be covered in copper coins to a depth of at least 400 meters.
· If you had a mole of pennies and wanted to buy kite string at the rate of a million dollars per inch, you would get your money's worth. After stretching your string around the Earth one million times, and to the Moon and back twenty-five times, you would have enough string left over to sell back at a penny an inch (a decided loss) to gain enough money to buy every man, woman and child in the US a $5000 automobile and enough gasoline to run it at 55 mph for a year. After those purchases, you would still have enough money left over to give every man, woman, and child in the whole world $6136.
Homework Question: Write your answer in at least 2 complete sentences.
How is a mole different than an atom?
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