Elements vs. Compounds What we see is not what we get
Elements vs.
Compounds
What we see is not what we get
Halogens
The halogens consist of the elements
in family VII
They are Fluorine, Chlorine, Bromine,
Iodine, and Astatine.
Most of them are gasses at room
temperature.
What were some of the properties
that you were able to find about the
Halogens?
Fluorine
Brown very reactive gas
Alkali MetalsThe alkali metals are in the first family
They consist of Lithium, Sodium,
Potassium, Rubidium, Cesium and
Francium.
They are all solid at room
temperature, and react vigorously
with water.
What were the properties of the Alkali
metals the you were able to find?
Meeting of the Minds
The most familiar
combination of a
alkali metal and
a halogen is
Sodium Chloride.
This is commonly
called salt
NaCl
Salt is Sodium
and Chlorine
combined
together in a
1 to 1 ratio
Sodium + Chlorine
= NaCl
Properties of NaCl
Melting point
800.8° C
Boiling point
1,465° C
Crystal Structure
Soluble in water
Density 2.165
g/ml
What are the properties of salt that
you know?
Things to Remember
The physical properties of compounds do not
match the physical properties of the elements
that make them up.
The chemical properties of compounds do not
match the chemical properties of the elements
that make them up.
Depending on bonding, elements can combine
in many different ratios to form a variety of
compounds from the same basic building blocks.