What Is a Mole? Reference Page
Purpose of What Is a Mole?
A mole is a basic concept in Chemical Engineering. It’s purpose is to determine the masses of reagents needed in chemical reactions. Unlike in Chemistry, where a mole is a mole is a mole, in Chemical Engineering engineers need to work with different mass units such as pounds-mass \((\mathrm{lb_m})\), tons, and kilograms. For each mass unit there is a corresponding mole. For a chemical species, the numerical value of a mole in a given mass unit doesn’t change with the mass unit, but the unit does. For example, with \(\mathrm{NaCl}\) that has a molecular mass of \(58.443\), a gram-mole (or simply mole) has a mass of \(58.443\ \mathrm{g}\), a pound-mole has a mass of \(58.443\ \mathrm{lb_m}\) and a ton-mole has a mass of \(58.443\ \mathrm{ton}\) (one might have to specify whether the ton is a long ton or a short ton).
The videos explain what a mole is and how it is used in basic Chemical Engineering calculations.
The Full Story Video
The Full Story Video examines common conceptions and misconceptions about moles before explaining what a mole is and how to use a mole. It is recommended for those who have not been exposed to moles before or who have struggled with understanding what a mole is or how it is used.
The Just The Facts Video
The Just The Facts Video gets straignt to explaining what a mole is and how it is used. It is recommended for those who have a reasonably good understanding of moles and are just looking for a refresher or a review.
Definitions
- Avogadro’s Number
- Avogadro’s number or the Avogadro Constant, \(N_\mathrm{A}\) is listed on the N.I.S.T. as having a value of \(6.022\ 140\ 76 \times 10^{23}/\mathrm{mol}\), where \(\mathrm{mol}\) is the gram mole.
- Gram Atom
- The gram atom is the name given to an Avogadro’s number of atoms. Compare with an Avogadro’s number of molecules, called the gram mole.
- Molar Mass
- The molar mass of a chemical compound is the ratio between the number of moles of a compound and its mass. See Wikipedia Molar mass for a more thorough explanation.
- Mole or Gram Mole
- A mole (abbreviation \(\mathrm{mol}\)) or gram mole (abbreviation \(\textrm{g-mol}\)) is the mass in grams of an Avogadro’s number of molecules of a chemical species. For example, a mole of \(\mathrm{NaCl}\) has a mass of \(58.443\ \mathrm{g}\).
- Pound Mass
- A pound mass is the mass that exerts a force of one pound force when accelerated at the standard gravitational acceleration rate of \(32.174\ \mathrm{ft/s^2}\). N.I.S.T lists the pound mass as being the same as \(0.453\ 592\ 37\ \mathrm{kg}\). It is abbreviated as \(\mathrm{lb_m}\).
- Pound Mole
- A pound mole (abbreviation \(\textrm{lb-mol}\)) is the mass equivalent in pounds mass of the molar mass of a chemical species. For example, a pound mole of \(\mathrm{NaCl}\) has a mass of \(58.443\ \mathrm{lb_m}\).
Additional Links
Preceding Videos
As of this writing the two sets of videos preceding this set are:
- Under Pressure Part 1 The Full Story, Just The Facts, Reference Page
- Under Pressure Part 2 The Full Story, Just The Facts, Reference Page
Following Videos
As of this writing the two sets of videos following this set are:
- Mass, Moles, and Mass and Mole Fractions The Full Story, Just The Facts, Reference Page
- Volume, Densit, Flow Rates The Full Story, Just The Facts, Reference Page
Other Links
- The Wikipedia discussion of the mole. The other mass unit moles are discussed under Similar units.