Moles

Moles

The Mole is the SI unit for amount of substance. It is used as a counting unit used to count a large number of atoms.

1 mol of atoms = Avogadro's number

• = 602 sextillion; 602,000,000,000,000,000,000,000
• 6.02x10²³

Molar Mass:

• The mass of 1 mol of a substance is called the molar mass
• Written in terms of grams per mole (g/mol)
• eg: Mercury (Hg) - 200.6 g/mol

Avogadro's number:

• Is the number of particles in exactly one mole of a pure substance
• Can be written as:
  • 6.022x10²³ particles/mol
  • 6.022x10²³ atoms/mol
  • 6.022x10²³ molecules/mol

Mole Conversions:

• Use the factor label method:
• Start with the end in mind
• List your given (put your given over 1)
• Use the appropriate conversion factor
• Check your units

mass to moles: (# of grams/1)( 1 mol/Molar Mass (g))

moles to mass: (# of moles/1)(Molar Mass (g)/1 mole)