[Mgs] list

[Paul Hunt]

Yes ZDDP is a compound, but it is obtained by the producer indicating he has
added specific concentrations of zinc and phosphorus to a base product.  Take
sea-water.  If you ignore all other compounds and constituents other than salt
and water, there is about 3.5% salt and 96.5% water.  Adding the two together
you get 100%.  Expressing things as a percentage is the same as expressing
them as 'parts per hundred'.  Parts per hundred is never or very rarely used
of course, but parts per thousand and parts per million are, the only
difference is they have more zeros but are used for convenience to express
very small quantities.  3.5% is the same as 35 parts per thousand or 35,000
parts per million.  The water would be 965 parts per thousand or 965000 parts
per million.  Add the two together and you get 100, 1000 or 100000 as
appropriate.

PaulH.
  ----- Original Message -----


  No. We are talking about ZDDP as a compound, not about the individual atoms
  of zinc and phosphorus.