Moles and Equations

A mole is defined as 6.02214076 × 10²³ of some chemical unit, be it atoms, molecules, ions, or others. The mole is a convenient unit to use because of the great number of atoms, molecules, or others in any substance.

Amedo Avogadro, an Italian scientist known as one of the founders of physical chemistry, was born. Avogadro studied the properties of electricity and liquids, but his best known work was with gases.

Relative Atomic Mass

The relative atomic mass the weighted average mass of naturally occurring atoms of an element on a scale where an atom of carbon-12 has a mass of exactly 12 units.

Relative Isotopic Mass

The mass of a particular isotope of an element on a scale where an atom of carbon-12 has a mass of exactly 12 units

Relative Molecular Mass

The relative mass of one molecule of the compound on a scale where the carbon-12 isotope has a mass exactly 12 units

Formula for ionic and Molecular for covalent

Relative Formula Mass

The relative formula mass of a substance made up of molecules is the sum of the relative atomic masses of the atoms in the numbers shown in the formula . Relative formula mass has the symbol, M.

Mass Spectrometry

Mass spectrometry (MS) is an analytical technique that is used to measure the mass-to-charge ratio of ions. The results are typically presented as a mass spectrum, a plot of intensity as a function of the mass-to-charge ratio.

-Multiply each isotopic mass by its percentage values

-Add the figures together

-Divide by 100

The mole and the Avogadro constant

The Avogadro constant is the proportionality factor that relates the number of constituent particles (usually molecules, atoms or ions) in a sample with the amount of substance in that sample. Its SI unit is the reciprocal mole, and it is defined as N_A = 6.02214076×10²³ mol⁻¹. One mole of the substance is the amount of substance that has the same number of specific particles, atoms, molecules or ions as there are atoms in exactly 12g of the carbon-12 isotope.