Basic Chemistry Concepts

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Here are some basic chemistry concepts.

Extensive Properties

properties of matter that depend on the quantity of the matter observed (volume, mass, heat).

Intensive Properties

properties of matter that are independent of the amount of matter observed (density, temperature).

Homogeneous mixtures:

uniform throughout and include such things as solutions

Hetrogeneous mixtures:

not uniform; components of the mixture vary in concentration throughout the mixture.

Qualitative Properties

subjective properties (colour, Odour, etc.)

Quantitative Properties:

Objective and empirical properties (weight, volume, etc.)


the degree of reproducibility of a measured quantity.


how close a measured value is to the actual value.


elements with the same number of protons but a different number of neutrons and a different atomic mass.

Atomic number

or (Z) is the number of protons in the nucleus of an atom. Atomic number is not the number of electrons in an atom, however, in an electronically neutral atom the number of electrons and protons happens to be the same.

Atomic mass

(fractional abundance of isotope 1)(mass of isotope 1)+ (fractional abundance of isotope 2)(mass of isotope 2) + . . . + (fractional abundance of isotope n)(mass of isotope n)

Avogadro Constant

number of elementary entities in a mole, 6.02x10^23 mol^-1

Theoretical Yield

the calculated quantity of product that one expects from given quantities of reactants.

Strong Acid

molecular compounds that are almost completely ionized in water.

Strong Base

one that is completely ionized in an aqueous solution.

Weak Acid:

one that is incompletely ionized in aqueous solution.


loss of electrons by a chemical spieces [Oil--> Oxidation is Losing]


gain of electrons by a chemical spieces [Rig--> Reduction is gaining]

Oxidizing Agent

causes a chemical species to lose electrons and get oxidized in the process.

Reducing Agent

causes a chemical species to gain electrons and get reduced in the process.