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Process in which a substance receives other. In absorption process's it is verified the absorption of gas or liquid by a solid or liquid. The absorbed substance is "infiltrated" in the substance that absorbes.


Compound that contains hydrogen, being able to free it in an aqueous solution. These aqueous solution always presents a pH lower than 7. The strength of an acid depends on the easiness that the hydrogen ion is solvated.


Process in which a substance (gas or liquid) is held in the surface of a solid. In the adsorption process it is verified the formation of a layer of gas or liquid on the surface of a solid. The adsorption can be chemical or physic. In the chemical adsorption, the adsorbed substance reacts with the adsorbent surface having the formation of chemical bounds. On the other hand, in physical adsorption there isn't the formation of chemical bounds. The molecules are adsorbed through Van der Walls forces.


Organic compound that contains chemical groups -OH.


Negatively charged ion. For instance, OH- is an anion.


Electrode where the electrons formation reaction happens (oxidation reaction).


The smallest amount of a chemical element that can exist maintaining the characteristic properties of it. The element atom is constituted by nucleus (protons and neutrons), surrounded by moving electrons.

  Atomic relative mass

Ratio between the atom mass of a certain element and 1/12 of the atom mass of carbon-12.



Measures the atmospheric pressure.


Device that generates electric energy by chemical reaction. A battery is made by two electrodes (cathode and anode) and an electrolyte.


Compound that when dissolved in water forms hydroxide ions (OH-). A base aqueous solution always has a pH higher than 7. The base aqueous solutions are designated by alkaline solutions.

  Calorific capacity

Amount of heat supplied to a substance in order to increase its temperature. The calorific capacity is defined as the amount of heat supplied (in Joules) to a certain mass of a substance (in Kg) so that the temperature of it increases (in Kelvin).


Positively charged ion. For instance, H+ is a cation.


Electrode that receives electrons (reduction reaction).


System in which one or more phases are dispersed in a medium. The dispersed phase presents dimensions Between mili and nano meters (10-3 a 10-9 m)


Heat transfer process in which heat is transferred from a fluid part to another by the movement of the own fluid. The convection can be natural (density) or forced (mechanical agitation).


Measure of the mass of a substance per unit of volume.


Mass transfer process in which compounds are mixed as a result of the random movement of their elements (atoms, molecules or ions).

  Ebullition point

Temperature in which the saturated vapor pressure of a liquid is equal to the external atmospheric pressure.


A conductor et the surface of which electron transfer to or from the surrounding solution takes place.


Solute specie whose solutions conduct electricity.


Atom elementary particle that has a negative charge and a mass two thousand times less than the mass of a proton or neutron.

  Electrolytic cell

Electrochemical battery that consume electricity.


Direct measurement of the disorder of a system.


State change from liquid to vapor.

  Fusion point

Temperature in which a solid passes from the solid state to the liquid state and vice-versa.

  Galvanic cell

Electrochemical battery that store electricity.

  Gravity point

Object point where we can suppose that all its mass is concentrated.



Element atom with a specific number of neutrons.




  Molar concentration

Number of moles of specie X in one liter of solution.


Group of interlinked atoms by one or more chemical bounds. The molecules can be constituted by atoms of same element (O2) or different elements (H2O).


Subatomic particle that is part of the atom nucleus. This doesn't transport any electric charge.


Movement of solvent molecules through a semi permeable membrane, from a less to a more concentrated solution.


Reaction in which there is electrons production.


Measure the acid or base strength of a solution. The pH is defined as -log[H+].


Molecules with high dimension that are constituted by repeat units (monomers).


Force exercised per unit of surface area. For instance, a Newton force exercised in a m2 surface is equivalent to a Pascal (pressure IS unit).


Subatomic particle that has positive charge.



Heat transfer process in which energy is transferred in electromagnetic waves form or photons.


Reaction in which electrons act as reactants.


Homogeneous mixture of two or more compounds.


Substance that is dissolved in a solvent.


Liquid in which the solute is dissolved.


Phase change from solid state to gaseous state. For instance, naphthalene is a solid that suffers sublimation.

  Surface tension

Force that acts on a surface per unit of length of the perpendicular surface to the force. The superficial tension is an intermolecular force that tends to minimize the liquid superficial area.




A gas with low pressure, having a minimum amount of atoms or molecules. The perfect vacuum is impossible to reach.


Resistance that a fluid exhibits to its movement or to the movement of bodies through it.






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