Zusammenfassung der Ressource
Elements
- An element is a simple substance that cannot
be split into anything simpler by chemical
reactions
- Atoms are the smallest particles of an element. Atomes of on
element are all the same but are different from atoms of all the
other elements
- All the elements are shown in the periodic table
- There are 117 known elements, each
element has a chemical symbol, wich i
usually one or two letters
- A symbol is written with the first letter as a
capital and the second letter in lower case,
these are examples
- Iron - Fe
- Aluminium - Al
- Oxygen - O
- Carbon - C
- Compounds
- Elements can join together to
make a compound
- The name of the compound
tells you the elements that are
in it
- Compounds made from two
elements always have a name
that ends in "ide"
- Carbon + Oxygen = Carbon Dioxide
- Sodium + Chlorine = Sodium Chloride
- Magnesium + Oxygen = Magnesium Oxide
- A chemical formula tells you the
name and number of atoms in a
compound, the smallest particle of
many compounds is called a
molecule
- Molecules are made up of groups of atoms,
some elements are also made of molecules,
for example, a molecule of oxygen contains
two atoms joined together - 02
- Water contains two atoms of hydrogen and
one of oxygen - H20
- Metals and non-metals
- The properties of a substance
describe the way the substance
behaves, or measurements that we
can make on it. Metal and
non-metals have different properties
- Non-metals
- Most are solids or gases
- Dull
- Brittle - Break easily and
can not bend very well
- Found on the right and
middle of the periodic table
- Poor conductors of heat
and electricity
- Metals
- Good conductors
of heat and
electricity
- Shiny
- Solids with a high melting point
- Mainly found on the
left-hand side and in the
centre of the periodic
table
- The metals are magnetic
- Re-use and recycling
- Materials can be
classified to the
properties.
- All the different materials in the world
are made up of about 90 different
elements, some useful materials occur
naturally, but others have to be
manufactured using chemical reactions
- In many cases, raw materials are
non-renewable. If we can recycle these
materials, then we reduce the demand for raw
materials. There may also be energy saving as
well
- A process that used recycled or renewable
materials is sustainable. Waste can also be
reduced by re-using objects such as glass
bottles or plastic bags