Download A mole Chemistry uses a special unit to represent the number of

A mole
Chemistry uses a special unit to represent the number of particles (atoms or molecules). This
unit is called a mole. Like a dozen represents 12, a mole represents 6.02 x 1023 particles. This
number (6.02 x 1023) is called Avogadro’s number.
Converting Number of Particles to Moles
Converting Moles to Number of Particles
Atomic mass units
The mass of a molecule or single atom is measured in atomic mass units (amu). Atomic mass
values can be found on the periodic table; for example the atomic mass of Carbon is 12.011 amu.
This value expressed in grams is equivalent to 1 mole of the atom. The molar mass of Carbon is
therefore, 12.011 g/mol.
To calculate the atomic mass of a compound, simply add the atomic masses of the individual
atoms in the compound. For example, H2O has 2 H atoms and 1 O atom, which add up
respectively to a molar mass of 18.0 g/mol (1.0 + 1.0 + 16.0).