Transcript Periods and Groups All of the elements in a period have the same number of Electron Energy Levels. The elements in a.

Periods and Groups
All of the elements in a period have the same number of Electron Energy Levels.
The elements in a group have the same number of electrons in their outer Electron Energy Level.
Slide 1
Metals
• Almost 75% of all elements are classified as metals.
• CONDUCTION:
– Metals are really good at conducting electricity and heat.
– Silver (Ag) and copper (Cu) are some of the most efficient metals
and are often used in electronics.
• REACTIVITY:
– Metals are very reactive. Some more than others, but most form
compounds with other elements quite easily.
– Sodium (Na) and potassium (K) are some of the most reactive
metals.
• CHEMICAL:
– Metals usually make positive ions when the compounds are
dissolved in solution.
– Metallic oxides make hydroxides (bases) (OH-) and not acids
when in solution.
– Sodium chloride (NaCl) when dissolved in water breaks apart into
sodium (Na+) and chlorine (Cl-). Sodium is the metal.
Slide 2
Alkali Metals
The far left column is GROUP ONE (Group I).
Hydrogen (H) is NOT in the family.
The members of the family include... Lithium (Li),
Sodium (Na), Potassium (K), Rubidium (Rb), Cesium
(Cs) and Francium (Fr).
They all have one electron in their outer shell. s1
That's one electron away from being happy (full shells).
Alkali Metals are Very REACTIVE.
Alkali metals are malleable, ductile, and are good conductors of heat and electricity.
The alkali metals are softer than most other metals.
Their light weight and physical properties separate them from other metals.
Alkali metals can explode if they are exposed to water.
Slide 3
Alkaline Earth Metals
• Less reactive than Alkali Metals
– Have 2 valence electrons and form a +2 charge.
– Electron configuration ends with a s2.
• Have higher densities and melting points
than Alkali Metals.
– Because of their reactivity, the alkaline metals are not
found free in nature.
– Magnesium and Calcium are most common and most
useful.
– Beryllium, Strontium, Barium, and Radium are more rare.
Slide 4
Transition Metals
Transition metals have complex electron
configurations.
They end with d and f electron orbitals.
They have a lot of electrons and distribute them in a
variety of ways. Have (+) charges and form cations.
Transition Metals are much less reactive than alkali
metals.
D-block transition metals are very common and useful.
F-block transition metals are more rare and less useful.
Chromium – very resistant to corrosion, hard, silvery color.
Iron – corrodes easily, very abundant and cheap, very strong and durable as steel.
Coinage metals – resistant to corrosion and colorful. Used for jewelry and money.
Lead – Dense, soft pliable metal, poisonous, very useful in electronics.
Lanthanides – little commercial use, expensive, used to color TV screens.
Actinides – generally radioactive. Used as nuclear fuel and for nuclear research.
Slide 5
Semi-metals
• Are the elements found along the stair-step
line that distinguishes metals from nonmetals.
• Have properties of both metals and nonmetals.
– Silicon and Germanium, are semi-conductors.
– This means that they can carry an electrical
charge under special conditions.
– This property makes semi-metals useful in
computers and calculators
Slide 6
Non-metals
• Non-metals are not able to conduct electricity or heat
very well.
• Non-metallic elements are very brittle, and cannot be
rolled into wires or pounded into sheets.
• The non-metals have no metallic luster, and do not
reflect light.
• The non-metals exist as gases (such as oxygen) or
solids (such as carbon) at room temperature.
Slide 7
The Boron Group
• Tend to lose three electrons and form
positive ions with + 3 charges.
– Its electron configuration end with s2p1.
• Aluminum is the most important element of
the group.
– It has a low density, but great strength.
– It does not corrode readily in air.
• Gallium has a low melting point and is used
in fire sprinklers.
Slide 8
The Carbon Group
• Group includes the element most central to life
and the element most central to modern
technology.
• Carbon is the basis for organic chemistry and
forms more compounds than any other element
except hydrogen.
• The maximum ionic charge is –4 or +4 making it
very versatile.
• Tin and lead usually have +2 ionic charges.
• More nonmetallic on average than Boron Group
elements.
• Lower members still distinctly metallic.
• Its electronic configuration ends with s2 p2.
Slide 9
The Nitrogen Group
• Nitrogen is a major component of air and is
essential to life.
– It makes up eighty percent of air on Earth.
– It is not very reactive.
– It used in fertilizer for plants.
• Phosphorus has three allotopes
– They are white phosphorus, black
phosphorus, and red phosphorus.
– Phosphorus is very active in air and burns
easily.
• Arsenic is poisonous.
• Its electronic configuration ends with s2 p3.
Slide 10
The Oxygen Group
• Oxygen, in Group VI of the Periodic
Table, makes up nearly half of the Earth's
crust by mass.
• Oxygen is present in air, and can form a
compound with almost every other
element.
• Sulfur can exist in many allotropic forms
at different temperatures.
• Its electronic configuration ends with s2 p4.
Slide 11
Halogens
Group VII is the home of the HALOGEN FAMILY.
The elements included are... Fluorine (F), Chlorine (Cl),
Bromine (Br), Iodine (I) and Astatine (At).
WHAT MAKES THEM ALIKE?
They have seven electrons in their outer shell.
They are all just one electron shy of having full
shells. Its electron configuration ends with s2 p5.
Halogen are very reactive with other elements.
When a halogen combines with another element the resulting compound is called a HALIDE.
One of the best examples of a halide is Sodium chloride (NaCl).
Slide 12
Noble Gases
The far right is also known as GROUP ZERO (Group 0).
This family has the happiest elements of all.
WHY ARE THEY HAPPY?
Happy atoms have full shells. s2 p6
All of the inert gases have full outer energy levels.
They rarely combine with other elements.
That is why they are called inert.
WHO'S IN THE FAMILY?
Helium (He), Neon (Ne), Argon (Ar), Krypton (Kr), Xenon
(Xe) and Radon (Rn).
Slide 13