Elements are simple made of the same type of
They cannot be
down chemically.
There are about
elements in total.
Most elements are metals. They are
in appearance and are
good
of heat and
Compounds are made from
or more elements chemically

Answer explain why it is not possible to deduce a complete order of reactivity.

What is true for a substance that releases energy

One way in which the useful metal copper is produced is by dissolving the mineral azurite, which contains copper(ii) carbonate, in concentrated sulfuric acid. the sulfuric acid reacts with the copper(ii) carbonate to produce a blue solution of copper(ii) sulfate. scrap iron is then added to this solution, and pure copper metal precipitates out because of the following chemical reaction: (s) (aq) (s) (aq) suppose an industrial quality-control chemist analyzes a sample from a copper processing plant in the following way. he adds powdered iron to a copper(ii) sulfate sample from the plant until no more copper will precipitate. he then washes, dries, and weighs the precipitate, and finds that it has a mass of .