The Mole Concept
- the extreme smallness of atoms and molecules makes it necessary to define a very large “standard sample”
- it is referred to as the MOLE
- it’s the SI base unit for amount of chemical substance
- one mole consists of 6.02 x 1023 atoms or molecules; it is known as Avogadro’s Number
- the mass of one mole of an element is the same as the atomic mass of the element
one mole of bromine, atomic mass 79.90 amu, has a mass of 79.90 g; this is called the molar mass
the molar mass of chromium, Cr, is 52.00 g/mol.
Types of Calculations:
(i) mass of 1.50 moles of chromium
(ii) # of moles in 5.00g of O2
(iii) determining the molar mass of a compound; what is the molar mass of CuSO4?
(iv) # of moles given a particular mass of a compound; how many moles is 56.00 g of NaCl?
(v) mass of a compound given a particular # of moles; determine the mass of 0.1 moles of H2SO4.