Presentation on theme: "1 The Mole. 2 How you measure how much? How you measure how much? n You can measure mass, n or volume, n or you can count pieces. n We measure mass in."— Presentation transcript:
1 The Mole
2 How you measure how much? How you measure how much? n You can measure mass, n or volume, n or you can count pieces. n We measure mass in grams. n We measure volume in liters. n We count pieces in MOLES.
3 Moles n Defined as the number of carbon atoms in exactly 12 grams of carbon- 12. n 1 mole is 6.02 x particles. n Treat it like a very large dozen n 6.02 x is called Avagadro’s number.
4 The Mole Song A mole is an animal that burrows in the ground Or a spot on your chin that you gotta shave around But there’s another kind of mole of interest to me That’s the kind of mole they use in chemistry A mole is a unit or have you heard Containing six times ten to the twenty-third That’s a six with twenty-three zeros at the end Much to big a number to comprehend Say you had a mole of pennies to distribute round the world Give to each of the five billion grown-ups, boys and girls There wouldn’t be a single soul down and out of luck Cause everybody in the world would get a trillion bucks Or say you had a mole of paper and stacked it towards the sky, Papers awful thin but that pile would get so high, It’d reach up into outer space, in fact I think you’d find It’d go up to the moon and back eighty billion times A mole is a unit or have you heard Containing six time ten to the twenty-third That’s a six with twenty three zeros at the end Much to big a number to comprehend Suppose a mole of marshmallows fell upon the planet Over each square inch of land and sea, think that you could stand it? That layer would be twelve miles high and of course block out the sun. We’re talking close to five million trillion tons Well maybe we could save ourselves if we all started eatin, One marshmallow each second, not two cause that’d be cheatin, With five billion people munchin, how long do you think it’d take? Forty million years – and that’s without a bathroom break A mole is a unit or have you heard Containing six time ten to the twenty-third That’s a six with twenty three zeros at the end Much to big a number to comprehend But say you had a mole of atoms, would the pile be immense? Should I say the answer now, or leave you in suspense? Well atoms are so very, very small you understand, You could hold a mole of atoms in the palm or your hand. So shake a little sugar in the middle of your palm Now you don’t want to spill it so try to stay calm You can hardly imagine and barely realize There are more atoms in that sugar than stars up in the sky A mole is a unit or have you heard Containing six times ten to the twenty third That’s a six with twenty-three zeros at the end Much to big a number to comprehend
5 Examples n How many atoms in 3.5 mole of Ca? 3.5 mole Ca x = 3.5 mole Ca x =
6 Practice n How many atoms in.67 mole of Be? ( ___ x )
7 Example n How many moles is 5.8x10 22 atoms of N? 5.8 x atoms x = 5.8 x atoms x = = mole N = mole N
8 Practice n How many moles is 7.9x10 24 atoms of P?
9 Measuring Moles n Remember relative atomic mass? n The amu was one twelfth the mass of a carbon 12 atom. n Since the mole is the number of atoms in 12 grams of carbon-12, n The decimal number on the periodic table is also the mass of 1 mole of those atoms in grams.
10 Molar Mass n The mass of 1 mole of an element in grams. n Molar Mass of carbon is g/mole
11 Examples n How many moles is 96.8g of Sr? 96.8g Sr x =
12 Practice n How many moles is 183 g of Ba?
13 Example n How many grams is.50 moles of Si? 0.50 moles Si x =
14 Practice n How many grams is.75 moles of Na?
15 Example n How many atoms in 35.5 g of Al? 35.5 g Al x x =
16 Practice n How many grams is 8.9 x10 23 atoms of Ni?