Elements

The elements, alone or in combinations, make up our bodies, our world, our sun, and in fact, the entire universe .

Periodic Table

 Information about an element can be gathered from its position on the period table.

Periodic Table

Metals

Properties of Metals

Metals appear to the left of the dark ziz-zag line. Most metals are solid at room temperature however Hg is liquid.

Properties of Metals

Metals have

luster

. This means they are

shiny

Properties of Metals

Ductile

metals can be drawn into wire.

Properties of Metals

Malleable metals can be hammered into sheets

Properties of Metals

Metals have a

high melting point

. Some are very dense.

Magnetic properties – Fe, Co, Ni, Nd

Properties of Metals

Conductors Metals are good conductors of electricity and heat

Properties of Metals

Chemical properties:



React by losing electrons to other atoms

 

corrosion may be very reactive-family 1 or lack reactivity like Au

ALKALI METALS

 Group 1 – soft and shiny  React by losing 1 electron, never found uncombined in nature   Na and K important elements for life Li – batteries and some medicines

ALKALINE EARTH METALS

 Fairly hard, gray-white, good conductors of electricity    React by losing 2 electrons More reactive than most metals but less than family 1 Mg and Ca most common

TRANSITION METALS

 Hard, shiny, good conductors of heat and electricity    Many form colorful compounds Less reactive; used in jewelry Fe – essential for hemoglobin production

METALS in groups 13-15

 Less reactive    AL used in cans and airplanes Sn – thin coating protects steel from corrosion Pb (poisonous) used in batteries

LANTHANIDES

• Soft, shiny, malleable metals with high conductivity • Used in alloys with more common elements • Found together in nature; difficult to separate because they share common properties

ACTINIDES

• Ac, Th, Pa, and U are found in nature • All others are synthetic elements made in particle accelerators

Nonmetals

  

Properties of Nonmetals

Nonmetals are found to the zig-zag . right of the dark Hydrogen, found above family 1 is a nonmetal. Many nonmetals are gases temperature. (Br is a liquid.) at room

Properties of Nonmetals

Nonmetals do not have luster; they are

dull

.

Properties of Nonmetals

Brittle

Nonmetals are brittle so they

break

easily.

This means nonmetals ARE NOT ductile or malleable.

Properties of Nonmetals

Nonmetals have low density

.

Properties of Nonmetals

 

have a low melting point. are poor conductors of

heat

and electricity.

Properties of Nonmetals

Chemical



Most are reactive



F is the most reactive element known

 

Family 18 rarely form compounds Usually gain or share electrons

Carbon Family • Gain or lose 4 electrons • Compounds made from C are found in all living things • Most fuels that are burned for energy contain C, coal, gasoline, oil Nitrogen Family • N and P gain or share 3 electrons • Atmosphere is 78% N 2 , a diatomic molecule • all living things need N but cannot process it • P is more reactive, always found in compounds in nature **Diatomic Molecule – two atoms of the same element bonded together

Oxygen • Usually gains or shares 2 electrons; O, S, Se • O is most abundant element in crust and 21% of atmosphere • O 2 • O 3 – diatomic molecule living things breathe – triatomic molecule; Ozone in upper atmosphere – screens out harmful radiation from the sun Ozone at ground level it is a dangerous pollutant – highly reactive Halogens – means salt-forming      Gains or shares 1 electron F Cl I – used to prevent tooth decay, non-stick pans Br – used to kill bacteria, NaCl, CaCl melts ice on roads – used in photographic film – medical uses

NOBLE/INERT GASES  Do not usually gain, lose, or share electrons    Found in small amounts in atmosphere He balloons Neon lights also made with Xe and Ar HYDROGEN • Doesn’t have a family because of its unique properties • 90% of the atoms of the universe • Only 1% of earth’s of mass of Earth’s crust, oceans, and atmosphere • Most is found in the form of water

Metalloids

Properties of Metalloids

Metalloids may be found clustered around the dark zig-zag line that separates

metals

and nonmetals .

Properties of Metalloids

Metalloids may have properties of both

metals

and

nonmetals

.

Properties of Metalloids

Metalloids are solids that can be

shiny

or dull .

Properties of Metalloids

Varying ability to conduct electricity depends on temperature , exposure to light, and impurities

Properties of Metalloids

Metalloids are brittle, hard and somewhat reactive

Metalloids



Si – combine with O to form sand; used to make glass



B – a compound of B and O is used during the glass-making process to make heat resistant glass; also used in cleaning materials



Useful as semiconductors which conduct under some conditions but not others computer chips-

Q: Where are metals found on the periodic table?

A: on the left side of the table Q: What are the physical properties of metals?

A: luster, ductile, malleable, good conductors of heat and electricity, high melting points, magnetic Q: What are the chemical properties of metals?

A: react by losing electrons to other atoms corrosion – the destruction of metal through oxidation tarnish Q: What are the properties of the alkali metals?

A: shiny and soft; very reactive- lose one electron; never found uncombined in nature

Q: What are the properties of the alkaline earth metals?

A: reactive, losing 2 electrons; Mg and Ca are the most common Q: What are the properties of the transition metals?

A: are less reactive; used in alloys Q: How are Pb, Sn, and Al used?

A: Pb is used to shield x-rays; Sn is used as a coating on steel cans to prevent corrosion; Al is used in airplanes and soda cans Q: Where are the lanthanides found on the periodic table and how are they used?

A: the first row beneath the table; used in alloys; hard to separate because they found together and have similar properties

Q: Where are actinides found and how are they unique?

A: The actinides are found in the bottom row beneath the periodic table. Only four exist in nature – U (92) is the last natural element. The others are synthetic, made in a lab often lasting only a few seconds because they are so unstable Q: Give an example of how the ductility of a metal could be used.

A: Cu is used to make wires that carry electricity.

Q: Why do cooking utensils often have wooden handles?

A: metals conduct heat; handles are wooden so hands don’t get burned Q: How are elements synthesized? A: a particle accelerator is used to smash nuclei together so that they combine to form a single nucleus

Q: Where are the non metals found on the periodic table?

A: found on the right side of the table Q: What properties are found among the nonmetals?

A: many are gases or dull, brittle solids; lower densities, are poor conductors of heat and electricity; readily form compounds except for group 18; gain or share electrons Q: Which nonmetal is liquid at room temperature?

A: Br Q: Compare the halogens and the noble gases?

A: Both groups are nonmetals, but halogens are very reactive while the noble gases are not.

Q: Where are the metalloids found on the periodic table?

A: on either side of the zigzag line Q: What are three uses of metalloids?

A: used in making glass; cleaning materials, and computer chips Q: What property makes certain metalloids useful as switches to turn small and electric current on and off.

A: some metalloids, semiconductors, conduct electricity under some conditions but not under others