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 cationsCu+ 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

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:

graphitecoaldiamondfullerenes

• 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”

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

orange-red 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