Element Families

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Element Families
Objectives
• Determine properties of elements
based on element family
relationships
• Classify elements based on electron
configuration
• Distinguish representative elements
and transition metals
Important Vocabulary
• Alkali metal
• Alkaline-earth metal
• Halogen
• Transition metal
• Synthetic metal
• Lanthanides
• Actinides
• Rare Earth metal
• Noble gases
• Inert
• Alloys
Hydrogen
• Is in a family by itself but is classified with the
nonmetals
• It is the most common element in the universe
• Has only one proton and one electron
• Is a component of organic molecules
• Fun Fact:
• When hydrogen forms a negative ion it is
called hydride
• When hydrogen forms a positive ion it is
called hydronium
The Alkali Metals
• Group 1 of the periodic table
• Who’s in this family?
• Are metals that react violently with water
• Have one valence electron, which makes them
VERY reactive
• Never found in nature as pure elements
• They are also good conductors of electricity
• Fun Fact: Lithium is the most reactive metal in
the entire periodic table
Element Profile--Sodium
• Sodium is so reactive that it has
to be stored in oil
• It reacts violently with water &
oxygen
• It is a soft and shiny metal
• One of its most common
compounds is NaCl, sodium
chloride, aka table salt
Properties of Alkali Metals
Alkaline-Earth Metals
• Group 2 in the periodic table
• Who’s in this family?
• They are also very highly reactive metals that
do NOT exist as pure elements in nature
• Have 2 valance electrons
• They are harder metals with higher melting
points than group 1 elements
• Fun Facts:
• Beryllium is found in emeralds
• Calcium is essential for muscle contraction
Element Profile--Magnesium
• Magnesium is the lightest of all structural
metals
• It is used to build some airplanes
• It activates many of the enzymes that speed
up processes in the human body
• It combines with many other elements to form
useful compounds such as, milk of magnesia &
Epsom salts
Transition Metals
• Make up group 3 through 12 in the periodic table
• Also known as the d-block elements
• Who’s in this family?
• They do NOT all have identical outer electron
configurations
• They lose different numbers of valence electrons
depending on the element they react with
• Have same properties as other metals
• Fun fact:
• Palladium, platinum and gold are nearly inert and
are found in nature as pure elements
Element Profile--Copper
• Copper (Cu) is often used for
electrical wiring & plumbing
• It is also found in pennies & a
famous American landmark
• Forms 2 different cations
Cu+
Cu2+
cuprous cupric
Element Profile--Tungsten
• Tungsten is used in light bulb
filaments
• Also known as Wolfram
• It is soft enough to be cut with
a hacksaw
• It has the highest melting point
of all metallic metals
• It forms 1 cation only!
W6+
Element Profile--Mercury
• Is the only metal that exists
naturally as a liquid at room
temperature
• Also known as hydrargyrum &
quicksilver
• It is used in thermometers,
barometers & other scientific
instruments
• It has 2 cation forms
Hg+
Hg2+
Synthetic Metals & Rare Earth
Metals
• Lanthanides are the rare Earth metals.
• They are naturally found but in really small
quantities
• Actinides are almost all synthetic metals
• That means they are man-made in a laboratory
Lanthanides
Are the top row at the bottom of the periodic table
All of them are found in nature except for Promethium
These elements fill the 4f orbital
They are transition metals, but are not grouped with
the others so as to keep the table narrow
• They are shiny metals with reactivity similar to the
alkaline-earth metals
• Fun fact:
• They are called lanthanides because they follow
the element lanthanum
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•
•
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Element Profile--Europium
• Most reactive of the rare earth elements
• Found in the minerals bastnäsite and monazite
• It has also been identified in the spectra of the sun and
certain stars
• It has been used to:
• Dope some types of glass to make lasers
• Screen for Down syndrome and some other genetic
diseases
• Make red phosphors for color televisions with
yttrium oxide
• It is priced about $1350/g
Actinides
• Fill the far bottom row of the periodic table
• Their electrons fill the 5f orbitals
• All synthetic metals except for actinium,
thorium, protactinium, & uranium
• Their nuclei are unstable and spontaneously break
apart
• Fun facts:
• They are named actinides because they follow
the element actinium
• All actinides are RADIOACTIVE!
Element Profile--Plutonium
• Is radioactive & artificially produced
• It is used in radioisotope thermoelectric
generators to provide electricity for space
probes that venture too far from the sun to
use solar power
• Fun fact:
• Plutonium is used to power the flux
capacitor in the DeLorean time machine
in the movie “Back to the Future”
Nonmetals
• Are found throughout the periodic table
• Groups 13-16, 17 & 18 and hydrogen
• Most of them are gases
• Exceptions are phosphorus, sulfur, carbon,
selenium & iodine which are solids
• Bromine is a liquid
Element Profile--Carbon
• Carbon (C) comes in 4 different forms:
graphite
coal
diamond
fullerenes
• It likes to form compounds
• Found in living and nonliving things
• Why do these forms of carbon look
different from each other?
Element Profile--Nitrogen
• It makes up 78% of the Earth’s
atmosphere
• 5th most abundant element in the universe
• Was discovered by the Scottish physician
Daniel Rutherford in 1772
• It is essential to plants
• Forms negative ions N3-
Halogens
Make up group 17 in the periodic table
Who’s in this family?
Most reactive group of nonmetals
They have 7 valence electrons (Halogens react with most
metals to produce salts
• They have a wide range of physical properties:
• Fluorine and chlorine are gases at room temp.
• Bromine is a liquid
• Iodine is a solids
• Fun Facts:
• The word halogen comes from Greek and means “salt
maker”
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Element Profile--Fluorine
• Fluorine (F) is the most reactive
nonmetal known
• It is a poisonous yellowish gas but also
can be found as a solid mineral
• It forms negative ions, F –
• It is used in toothpastes & certain
water supplies
Noble Gases
• Are from group 18
• Who’s in this family?
• Have 8 valence electrons
• They have very LITTLE reactivity so, chemists
once called them inert gases
• Fun Facts:
• Excited neon atoms only produce an orangered light
Element Profile--Argon
• Aragon (Ar) was the first noble gas to be
identified in 1894
• Discovered by William Ramsay
• Used to fill light bulbs because it prevents
filaments from burning
• Name is derived from Greek word for lazy
Metalloids
• Are intermediate conductors of heat &
electricity
• Also known as semiconductors
• Include only 7 elements: Boron, Silicon,
Germanium, Arsenic, Antimony, Tellurium &
Astatine
• They are metallic-looking brittle solids
• Being too brittle to have any structural uses,
the metalloids and their compounds instead find
common use in glasses, alloys and
semiconductors.
Element Profile--Silicon
• Silicon (Si) accounts for 28% of the mass of
Earth’s crust
• Makes up sand, quartz, & glass
• Used in the internal parts of computers
Other Properties of Metals
• Melting points vary widely
• Tungsten has the highest melting point of 4322°C
• Mercury has the lowest melting point at -39°C
• Metals can mix with one or more other elements to
form alloys
• Alloys have different properties than the metals that
compose them
• Examples:
• Brass which is a mixture of copper & zinc
• Sterling silver is a mixture of copper & silver
• Steel is a mixture of iron , carbon, manganese
and nickel
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