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WHAT IS A MOLE?. Image from: http://www.animationlibrary.com/sc/163/Other_Rodents/?page=7. Info modified from: http://genchem.chem.wisc.edu/sstutorial/FunChem.htm. COUNTING ATOMS. Atoms are too small to count individually Use a counting unit called Avogadro's number.
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WHAT IS A MOLE? Image from: http://www.animationlibrary.com/sc/163/Other_Rodents/?page=7 Info modified from: http://genchem.chem.wisc.edu/sstutorial/FunChem.htm
COUNTING ATOMS • Atoms are too small to count individually • Use a counting unit called Avogadro's number • Avogadro's number = 6.02 X 1023 atoms
WHAT IS A MOLE? Just as an amount of 12 is described by the term dozen, Avogadro's number is described by the term mole. A dozen eggs is 12 eggs; a mole of atoms is 6.02 X 1023 atoms. http://images.jupiterimages.com/common/detail/84/83/23048384.jpg http://www.animationlibrary.com/sc/163/Other_Rodents/?page=7
Avogadro's number can be used to count anything. You could have a mole of apples or a mole of Ping-Pong balls. You can get some idea of the magnitude of Avogadro's number by considering that a mole of Ping-Pong balls would cover the surface of the Earth with a layer approximately 60 miles thick. http://farm1.static.flickr.com/34/123891179_3c553b3dba.jpg
Equally important:one mole of a substance has a mass in grams equal to the formula weight of that substance. • EX: one mole of glucose (C6H12O6) • contains 6.02 X 1023 molecules of glucose • has a mass in grams equal to 180 g (12 X 6 + 1.0 X 12 + 16 X 6 ) http://www1.istockphoto.com/file_thumbview_approve/3055983/2/istockphoto_3055983_sugar_pile.jpg
MOLARITY =a measure of concentration of a solution given in moles/L Example: A 1.0 M solution of glucose is made by dissolving 180 g of glucose in enough water to equal 1 L How would you make a 0.5 M glucose solution? a 0.1 M glucose solution?
THINK ABOUT IT? If you ADD 180 g of glucose TO 1 L of water, do you have a 1 M solution? YOU WILL END UP WITH MORE THAN 1 L of SOLUTION + http://www1.istockphoto.com/file_thumbview_approve/3055983/2/istockphoto_3055983_sugar_pile.jpg http://www.a3bs.com/imagelibrary/U14205/mechanics/U14205_graduated-cylinder-100-ml.jpg http://mrsdlovesscience.com/measure.html
VOLUMETRIC FLASK • Add your sugar • Fill up to 1 L mark →