Dimensional Analysis
A calculation method that tracks and cancels units through a chain of conversion factors to reach the required quantity.
Formula / equation
given quantity × (desired unit / given unit) = answer
Unit
Various
In depth
Also called the factor-label method, it turns most stoichiometric problems into unit bookkeeping: if the units of the answer come out right, the arrangement of the numbers is almost certainly right too. It also serves as a rapid check on any derived equation, since both sides must carry identical dimensions.
Examples in the real world
Converting 25.0 g of NaOH to moles: 25.0 g × (1 mol / 40.00 g) = 0.625 mol.