chemistry technology

Most municipalities must use a source of water in which the probability of pollution is rather high. Certainly, all our natural rivers and lakes and even the water stored in most reservoirs may be subjected to pollution,  and  generally  cannot  be  considered...

A  systematic  nomenclature  was  devised  towards  the  end  of  the  18th  century.  Elements  already known  retained  their  old  names,  e.g.  silver,  tin,  gold,  mercury,...

Laboratories have now become indispensable in schools, factories and research institutes to test, confirm, or demonstrate on a small scale, phenomena and processes which occur in nature or which may find application in industry or be of importance to science. The equipment of a...

Hydrocarbons   are   compounds   containing   only   carbon   and   hydrogen   atoms.   The   simplest hydrocarbon is methane, CH4. Its molecules are tetrahedral, the four hydrogen atoms lying at the corners of a regular tetrahedron...

Every chemical reaction requires some time for its completion, but some reactions are very fast and others  very  slow.  Reactions  between  ions  in  solution  without  change  in  oxidation  state  are  usually...

Practical   chemistry   includes   many   special   techniques   for   the   isolation   and   purification   of substances.  Some  substances  occur  very  nearly  pure in  nature,  but...

If sugar and water, two pure substances, are mixed together, a solution result, uniform throughout in  its  properties,  in  which  the  sugar  can  neither  be  seen  with  a  microscope  nor  filtered  out....

Different  materials  may  be  distinguished  by  their  properties,  the  most  obvious  of  which  is  the physical state, or state of aggregation, on the basis of which all materials are classified as solids,...

Water is one of the most important of all chemical substances. It is the chief constituent of living matter. Its physical properties are strikingly different from those of other substances. Ordinary water is impure, it usually contains dissolved salts and dissolved gases, and sometimes...

Hydrogen,  the  first  element  in  the  periodic  table,  is  a  very  widely  distributed  element.  Its  most important  compound  is  water,  H2O.  Hydrogen  is  found...

Chemistry is the science of substances - of their structure, their properties, and the reactions that change them into other substances. The study of chemistry may be divided into the following branches: - General chemistry, which is an introduction to the entire science. - Qualitative...