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1)(1.0 x 109)/(1.0 x 1023) = 2) How many moles are in 40.96 grams of nitrate ions?
1.0 x10-14
40.96 g NO3-
( g NO3-)
1
62.01
( mole NO3-)
= 0.6605 mole NO3-
Take out your PT and
Molar Highway
moleskito
moleism
moleodic
What do you get when you have a bunch of moles acting like idiots?
What kept Avogadro in bed for two months?
a tiny molelike creature with wings which drinks the blood of anyone who doesn't remember when Mole Day is
the continual reverence of moles
a word describing the Mole Day songs which are played over the loudspeaker
A bunch of Moleasses
Moleonucleosis
Multistep Conversions
Ex 1. How many molecules of CO2 are there
in 1.50 moles of CO2 ?
1.50 mole CO2
= 9.03 x 1023 molecules of CO2
( mole CO2 )
6.02 x 1023( molecules CO2 )
1
EX 2: How many moles of Na are there in 4.50 x 105 atoms of Na?
4.50 x105 atoms Na ( ) ( )
= 7.48x10-19 moles Na
6.02 x 1023 atoms Na
mole Na1
Mass compound in sample
# molecules compound in
sampleNeed:
1 mole = 6.02 x 1023 particles
Need:
molar mass of compound
The Molar Highway
Finding Various Quantities using The Mole
1 mole of a compound
3. Two scientists engage in a weight-lifting competition to see who is stronger (HOT!!!) Avagadro can bench press 7.85 x 1025 atoms carbon Einstein can bench press 6.78 x 1024 atoms einsteinium. Who can bench press the greatest mass?
( atoms C)6.02 x 1023
6.78 x 1024 atoms Es
7.85 x 1025 atoms C
( atoms Es)6.02 x 1023
( mole C)1
( mole Es)1
( mole C)1
( mole Es)1
( g C)
= 1570 or 1.57 x 103 g C
12.01
( g Es)
= 2840 or 2.84 x 103 g Es
252
Mass compound in sample
# molecules compound in
sample
Need:
1 mole = 6.02 x 1023 particles
Need:
molar mass of compound
The Molar Highway
Finding Various Quantities using The Mole
1 mole of a compound
# atoms or ions in sample
Need:
# of that atom or ion in
compound
4. Are there more nitrate ions in 4.00 x 1014 molecules Al(NO3)3 OR 2.00 x 1014 molecules of KNO3?
2.00 x 1014 molecules of KNO3
4.00 x 1014 molecules Al(NO3)3
molecule Al(NO3)3
molecule KNO3
( NO3- ions)
( NO3- ion)
3
1
1
1
= 1.20 x 1015 NO3- ions
= 2.00 x 1014 NO3- ions
Mass compound in sample
# molecules compound in
sample
Need:
1 mole = 6.02 x 1023 particles
Need:
molar mass of compound
The Molar Highway
Finding Various Quantities using The Mole
1 mole of a compound
moles of element or ion in the compound
# atoms or ions in sample
Need:
# of that atom or ion in
compoundNeed:
# of that atom or ion in
compound
5. A sample of 16.2 grams of MgBr2 and a sample of 21.0 grams of AgBr are arguing over who contains more moles
of the element bromine. Who is correct?
( g MgBr2) 184.11
21.0 g AgBr
16.2 g MgBr2
( g AgBr)
( mole MgBr2)1
( mole AgBr )1
( mole MgBr2)1
( mole AgBr)1
( mole Br)
= 0.176 mole Br
2
( mole Br)
= 0.112 mole Br
187.77
1
6. A sample of 3.9 x 1019 strontium chloride molecules contains how many milligrams of chlorine?
3.9 x 1019 molec. SrCl2 (2 atoms Cl ) (1 mole Cl) ( 35.45 g Cl) ( 103 mg Cl) (1 molec SrCl2) (6.02 x 1023 atoms Cl) (1 mole Cl)( 1 g Cl)
4.6 mg chlorine
7. The chemical tryptoline is a serotonin reuptake inhibitor. 76.71%C 7.02%H, 16.27%N.
a. Determine the empirical formula, which is also the molecular formula.
Answer (work shown on board): C11H12N2
b. How many atoms of hydrogen would be found in 4.5 x 10-6g of tryptoline?
(done on board) answer: 1.9 x 1017 atoms H
Moles of Water Activity
