Masses and moles
description
Transcript of Masses and moles
![Page 1: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/1.jpg)
Masses and moles
Not that kind of mole
![Page 2: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/2.jpg)
Re-mem-memRe-mem-mem-member…
K19
39.0983
Potassium
Average atomic mass, in amu/atom
![Page 3: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/3.jpg)
Re-mem-memRe-mem-mem-member…
K19
39.0983
Potassium
Assume the most common isotope has 39 p+n (19p and 20n)—but there are some heavier ones.
![Page 4: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/4.jpg)
And now, for something completely different.
• Def:
1 mole=6.02 x 1023 particles
Not that kind of mole
![Page 5: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/5.jpg)
As a conversion factor• 2.7 moles Ar = _?_atoms Ar
• 1.5 x 1021 molecules H2O=__?__moles H2O
.
![Page 6: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/6.jpg)
As a conversion factor• 2.7 moles Ar = _?_atoms Ar
2.7 moles Ar x 6.02 x 1023 atoms Ar =
1 mole Ar
• 1.5 x 1021 molecules H2O=__?__moles H2O
1.5 x 1021 molecules H2O x 1mole H2O =
6.02 x 1023molecules H2O
![Page 7: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/7.jpg)
As a conversion factor• 2.7 moles Ar = _?_atoms Ar
2.7 moles Ar x 6.02 x 1023 atoms Ar =
1 mole Ar
• 1.5 x 1021 molecules H2O=__?__moles H2O
1.5 x 1021 molecules H2O x 1mole H2O =
6.02 x 1023molecules H2O
1.6 x 1024 atoms Ar
.0025 moles H20
![Page 8: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/8.jpg)
6.02 x 1023
![Page 9: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/9.jpg)
6.02 x 1023
• Avogadro’s number.
• Amadeo Avogadro.
• He suggested that there is a number.
• The number is larger than he expected.
![Page 10: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/10.jpg)
The greatest conversion of all time!
1 amu X 6.02 x 1023 = 1 gram
atom X 6.02 x 1023 mole
Avogadro’s number!
![Page 11: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/11.jpg)
• Avogadro’s number is also the conversion from amu’s to grams.
• Both sets of units define the mole.
![Page 12: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/12.jpg)
What is the mass?
• .0582 mol Ni
• 12.0 mol Ne
• 4.80 x 10 25 atoms Xe
• 1.24 x 10 21 atoms Au
![Page 13: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/13.jpg)
What is the mass?
• .0582 mol Ni
• 12.0 mol Ne
• 4.80 x 10 25 atoms Xe
• 1.24 x 10 21 atoms Au
Convert to moles
first!
![Page 14: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/14.jpg)
What is the mass?
• .0582 mol Ni
3.42 g Ni
• 12.0 mol Ne
242 g Ne
• 4.80 x 10 25 atoms Xe
10500 g Xe
• 1.24 x 10 21 atoms Au
.406 g Au
![Page 15: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/15.jpg)
What is the mass?
• 2.4 mol He
• 9.03 x 10 23 atoms K
![Page 16: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/16.jpg)
How many moles?
• 18.3 g Sr
• 4.8 g Ar
• 4.03 x 10 23 formula units of iron (III) oxide
• 7.24 x 10 21 molecules sulfur hexaflouride
![Page 17: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/17.jpg)
How many moles?
• 18.3 g Sr
.209 mol Sr
• 4.8 g Ar
.12 mol Ar
• 4.03 x 10 23 formula units of iron (III) oxide
.669 mol Fe2O3
• 7.24 x 10 21 molecules sulfur hexaflouride
.012 mol SF6
![Page 18: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/18.jpg)
How many moles?
• .130 g Ag
• 1.42 x 10 24 molecules nitrogen trichloride
![Page 19: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/19.jpg)
Pop quiz
• If 1 mole of hydrogen atoms (H) has a mass of 1.0078 g, what is the mass of 1 mole of hydrogen molecules (H2)?
![Page 20: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/20.jpg)
Pop quiz
• If 1 mole of hydrogen atoms (H) has a mass of 1.0078 g, what is the mass of 1 mole of hydrogen molecules (H2)?
• I hope you answered “Twice that mass.”, or 2.0156 g
![Page 21: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/21.jpg)
Formula masses
• If I give you a formula, you add the masses of the atoms represented to get the formula mass.
• The units are grams/mole
![Page 22: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/22.jpg)
What is the formula mass of…
• LiCl
• BaF2
• K2SO3
• Fe2(Cr2O7)3
• Na2HPO4 • 7H2O
![Page 23: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/23.jpg)
What is the formula mass of…
• Gold (I) fluoride
• Lithium oxide
• Cobalt (II) cyanide
• dinitrogen trisulfide
• tetraphosphorus hexoxide
![Page 24: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/24.jpg)
PS
• The subscripts in a formula can be read:
K2SO3
There are two potassium atoms in a formula unit
of potassium sulfite
There are two moles of potassium
in a mole of potassium sulfite
or
![Page 25: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/25.jpg)
PS
• The standard molar volume for a gas is:
at STP
22.4L/mol
22.4L/mol
STP =standard temperature and pressure
= 273k, 1.00 atm
![Page 26: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/26.jpg)
PS
is about22.4 L
![Page 27: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/27.jpg)
Mole conversions
![Page 28: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/28.jpg)
Mole conversions
Mass Moles
![Page 29: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/29.jpg)
Mole conversions
Mass Moles
Use the formula mass
![Page 30: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/30.jpg)
Mole conversions
Mass Moles
FM in grams = 1 mole
![Page 31: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/31.jpg)
Mole conversions
Particles Moles
![Page 32: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/32.jpg)
Mole conversions
Moles
Use Avogadro’s number
Particles
![Page 33: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/33.jpg)
Mole conversions
Moles
6.02 x 10 23 particles = 1 mole
Particles
![Page 34: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/34.jpg)
Mole conversions
MolesVolume of a gas at STP
![Page 35: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/35.jpg)
Mole conversions
Moles
Use the molar volume
Volume of a gas at STP
![Page 36: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/36.jpg)
Mole conversions
Moles
22.4 L gas at STP = 1 mole
Volume of a gas at STP
![Page 37: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/37.jpg)
Mole conversions
Moles
Volume of a gas at STP
Particles
Mass
Use the formula mass
Use Avogadro’s
number
Use the molar volume
![Page 38: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/38.jpg)
Styrene: an organic molecule, C8H8
1. What is the molecular weight of styrene?2. What is the empirical formula of styrene? 3. How much does 1.000 mole of styrene
weigh? 4. How much does 1.54 pmole of styrene
weigh? 5. How much many moles in 9.67 kg of
styrene? 6. How many moles in 84.6 mg of styrene?
![Page 39: Masses and moles](https://reader035.fdocuments.us/reader035/viewer/2022062304/5681399b550346895da1356c/html5/thumbnails/39.jpg)
Styrene: an organic molecule, C8H8
1. What is the mass % of C in styrene?
2. What is the mass % of H in styrene?
3. An unknown material is recovered from the Delaware River. Results from analysis of it are Carbon 92.26% Hydrogen7.74% Is it styrene?
4. The molecular weight of this compound is 78.11 grams per mole. What is its molecular formula?