In chemistry and physics a mole describes an amount of a substance in grams equal to its atomic mass. For example, one mole of aluminum has a mass of 13 grams since it has an atomic mass of 13. Also, one mole of a substance contains Avogadro's number of atoms, namely 6.02 times 10 to the power 23. The molarity, or concentration of a solution, equals the number of moles in the solution divided by its volume. Conversion between moles, molarity and volume is performed frequently in science problems.
Calculate the molarity of a solution in moles per liter, given moles and volume in liters, by dividing the number of moles by the volume. For example, a 5.0 liter solution containing 10.0 moles has a molarity of 2.0 moles per liter.
Determine the number of moles in a solution, with molarity and volume known, by multiplying molarity in moles per liter by the volume in liters--an example being a 2.0 liter solution with a molarity of 3.0 moles per liter. There are 6.0 moles in the solution.
Compute the volume of a solution in liters, given the number of moles and molarity, by dividing the number of moles by the molarity in units of moles per liter. For example, a solution containing 6.0 moles and a having a molarity of 3.0 moles per liter has a volume of 2.0 moles per liter.
About the Author
William Hirsch started writing during graduate school in 2005. His work has been published in the scientific journal "Physical Review Letters." He specializes in computer-related and physical science articles. Hirsch holds a Ph.D. from Wake Forest University in theoretical physics, where he studied particle physics and black holes.