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The Mol. The Atomic Mass Unit (amu). 1. The atomic mass Standard. 1 12. 2. the mass of an atom of carbon-12. Recently, the designation amu has been changed to the Dalton (D). mass of 28 Si atom mass of 12 C atom. = 2.331411. Observed:.
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The Atomic Mass Unit (amu) 1 The atomic mass Standard 112 2 the mass of an atom of carbon-12 Recently, the designation amu has been changed to the Dalton (D) mass of 28Si atom mass of 12C atom = 2.331411 Observed: Isotopic mass 28Si = measured mass ratio x mass of 12C Thus: =2.331411 x 12.0000 amu = 27.9693
The Mole The amount of a substance that contains the same number of fundamental units as there are atoms in exactly 12 g of carbon-12 ( 12C).
The Mole (mol) Type of matter Fundamental Unit (1)6.022 x 10 23 fundamental units of matter Elemental (monatomic; e.g. He, Fe, Xe) Atom Elemental (molecular; e.g. O2, H2, P4) Molecule Compounds , covalent ( e.g. H2O, ICl3) Molecule Formula Unit Compounds, ionic (e.g. NaCl, Al2O3 ) 6.022 x 1023 atoms He mol He 6.022 x 1023 formula units mol Al2O3 1 mol He: 1 mol Al2O3: 6.022 x 1023 molecules H2O mol H2O 1 mol H2O:
The Mole (mol)Elemental Matter That quantity of matter possessing a mass equivalent to the atomic weight of an element expressed in grams. (2). (monoatomic elements) 80 Hg 200.59 10 Ne 20.179 Ne Atomic Wt. ( avg. mass of Ne atoms): 20.179 amu Hg Atomic Wt.: 200.59 amu Mass of 1 mol Hg atoms: 200.59 g Mass of 1 mol Ne atoms: 20.179 g -or- 200.59 g Hg mol Hg -or- - 20.179 g Ne mol Ne
g Cu mol Cu atoms Cu How many atoms are found in 0.211 g of Cu? atoms Cu x mol Cu mol Cu x g Cu g Cu = atoms Cu 6.022 x 1023atoms Cu x mol Cu mol Cu x 63.546 g Cu 0.211 g Cu = 2.00 x 1021 atoms Cu
What is the mass of 1 atom of Ag? atom Ag mol Ag atoms g Ag g Ag x mol Ag mol Ag x atom Ag atom Ag = g Ag 107.9 g Ag x mol Ag mol Ag x 6.022 x 1023atoms Ag 1 atom Ag = 1.792 x 10-22 g Ag
mol Hg g Hg How many grams is 0.004986 mols Hg? g Hg mol Hg x = g Hg mol Hg 200.59 g Hg 0.004986mol Hg x = 1.000 g Hg mol Hg
Which is the larger number: • The number of human beings on earth ( approx. 6.5 billion or 6.5 x 109) • The number of Cu atoms in a single copper crystal (0.0006355 g Cu) .
The Mole (mol)Compounds That quantity of matter possessing a mass equivalent to the formula weight expressed in grams. (2). (compounds) Al2O3 H2O2 Al2O3 Formula Wt: ( avg. mass of one formula unit): 102 amu H2O2 Formula Wt : (avg mass of a molecule): 34.016 amu Mass of 1 mol Al 2O3 : 102. g Mass of 1 mol H2O molecules: 34.016g -or- 102. g Al 2O3 mol Al 2O3 -or- - 34.016 g H2O2 mol H2O2
Molar Relationships 20 Ca 40.08 O H H O H2O2 6.022 x 1023 atoms Ca 6.022 x 1023 molecules H2O2 mol Ca mol H2O2 40.08 g Ca 34.0 g H2O2 mol Ca mol H2O2
Molecular Formula Shows the exact number of atoms of each type in a molecule 3 S4Cl2 Coefficient: Indicates the number of molecular units Subscripts: Indicate the number of atoms of each kind in the molecular unit
Molecular Formula Shows the number of mols of atoms of each type in one mol of molecules 3 S4Cl2 Coefficient: Indicates the number of mols of molecular units Subscripts: Indicate the number mols of atoms of each kind inone mole of molecules 4 mols S mol S4Cl2 2 mols Cl mol S4Cl2 3 molsS4Cl2 of molecules
Molecular Formula Shows the number of mols of atoms of each type in one mol of molecules 3S4Cl2 Coefficient: Subcripts: Indicates the Indicate the number mols number of mols of atoms of each kind in molecular units one mole of molecules 4 mols S 2 mols Cl 3 molsS4Cl2 mol S4Cl2 mol S4Cl2
Stoichiometry Quantitative relationships expressed in the formula of a compound or molecular element.
Stoichiometry in Compounds Al2(SO4)3 7 H2OMo(CO)6 CH3(CH2)7 OH 2 Al atoms 6 CO molecules 8 C atoms 1 Al2(SO4)3 7 H2O 1 Mo(CO)6 molecule 1 CH3(CH2)7 OH (formula unit) molecule 7 H2O molecules 1 Mo atom 18 H atoms 1 Al2(SO4)3 7 H2O 1 Mo(CO)6 molecule 1 CH3(CH2)7 OH (formula unit) molecule 7 H2O molecules 1 Al2(SO4)3 formula unit
Stoichiometry in Compounds(mols) Al2(SO4)3.7 H2O 2 Al atoms 2 mols Al atoms 1 Al2(SO4)3 7 H2O unit 1 mol Al2(SO4)3 7 H2O formula units 7 H2O molecules 7 mols H2O mol ecules 1 Al2(SO4)3 7 H2O unit 1 mol Al2(SO4)3 7 H2O formula units 7 H2O molecules 7 mols H2O molecules 1 Al2(SO4)3 unit 1 mol Al2(SO4)3 unitss
g S4Cl2 mol S4Cl2 mol S g S mol S4Cl2 mol S g S gS4Cl2xx x g S4Cl2 mol S4Cl2 mol S mol S4Cl2 4mol S 32.06 g S 4.979 g S4Cl2 x x x = 199.1g S4Cl2 1 mol S4Cl2mol S = 3.207 g S
How many grams CO will be obtained when 0.5412 g Mo(CO) 6 decomposes? Mo(CO) 6 (s) Mo(s) + 6CO(g)
g Mo(CO) 6 mol Mo(CO) 6 mol CO g CO mol Mo(CO) 6 mol CO g CO g Mo(CO) 6 x x x g Mo(CO) 6 mol Mo(CO) 6 mol CO mol Mo(CO) 6 6mol CO 28.01g CO 0.5412 g Mo(CO) 6 x x x 264.00g Mo(CO) 6 1mol Mo(CO) 6 1mol CO = 0.3445 g CO
How many grams H2O will be obtained when 5.950 g Al2(SO4)3. 7 H2 O are heated? Al2(SO4)3. 7 H2 O (s) Al2(SO4)3 (s) + 7 H2 O(g)
g Al2(SO4)3. 7 H2 O mols Al2(SO4)3. 7 H2 O mols H2 O g H2 O mol Al2(SO4)3. 7 H2 O mols H2 O g Al2(SO4)3. 7 H2 O x x x . . . g Al2(SO4)3. 7 H2 O mol Al2(SO4)3. 7 H2 O g H2 O x = g H2 O mol H2 O 1 mol Al2(SO4)3. 7 H2 O 7 mols H2 O 5.950 gAl2(SO4)3. 7 H2 O x x x 318.1 g Al2(SO4)3. 7 H2 O 1 mol Al2(SO4)3. 7 H2 O 18.01 g H2 O x = 2.358 g H2 O 1 mol H2 O
How many grams of hydrogen atoms are contained in 50.0 g H2O? How many grams C atoms are provided by 12.22 grams of propane ( C3 H8)?
How many grams of hydrogen atoms are contained in 50.0 g H2O? 1 molH2O 2 mols H 1.008 g H 50.0 H2O x x x = 5.60 g H 18.0 g H2O 1 mol H2O mol H How many grams C atoms are provided by 12.22 grams of propane ( C3 H8)? 1 molC3 H8 3 mol C 12.22 g C3 H8 x x x ... 44.0 g C3 H8 1 mol C3 H8 12.011 g C x = 1.00 g C mol C
How many grams of potassium will be found in 0.3159 g of potassium bicarbonate?