MOLAR MASS OF A SUBSTANCE

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MOLAR MASS OF A SUBSTANCE

• The molar mass of a substance is the SUM of the
  ATOMIN MASS NUMBERS of ALL the atoms in the
  substance.
• If the substance is an atom, the mass is called
  ATOMIC MASS
• If the substance is a compound, the mass is
  called molar mass or gram formula mass.
• The molar mass of a substance is in the units
  grams/mole and is NOT affected by coefficients.
• The molar mass is an INTENSIVE PROPERTY, and is
  constant despite the size of your sample.

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CALCULATION OF MOLAR MASS
Example, calculate the molar mass of KMnO4
K
Mn
O
LIST ELEMENTS HERE
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CALCULATION OF MOLAR MASS
LIST SUBSCRIPTS
K 1
Mn 1
O 4
LIST ELEMENTS HERE
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CALCULATION OF MOLAR MASS
LIST SUBSCRIPTS
MULTIPLY
K 1 X
Mn 1 X
O 4 X
LIST ELEMENTS HERE
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CALCULATION OF MOLAR MASS
LIST SUBSCRIPTS
MULTIPLY
INSERT ATOMIC MASS FROM PERIODIC TABLE
K 1 X 24.30 G/MOL
Mn 1 X 54.93 G/MOL
O 4 X 15.99 G/MOL
LIST ELEMENTS HERE
6
CALCULATION OF MOLAR MASS
LIST SUBSCRIPTS
MULTIPLY
INSERT ATOMIC MASS FROM PERIODIC TABLE
K 1 X 24.30 G/MOL 24.30 G
Mn 1 X 54.93 G/MOL 54.93 G
O 4 X 15.99 G/MOL 63.96 G
LIST ELEMENTS HERE
Add SUBTOTALS