2.2 Using the Periodic Table

Elements can be divided into three broad classes based on their general properties:metals, nonmetals and metalloids.

Most elements are metals.Metals

Are good conductors of electricityAre able to reflect light when cleaned

or cutAll metals, except mercury, are solid

at room temperature.Most metals are ductile and malleable

Nonmetals are elements that tend to have properties that are the opposite of metals.Most non metals are gasses at room

temperature Sulfur & Phosphorous are solids at

room temperatureBromine is a brown liquid.

Nonmetals are generally poor conductors of electricity and heat.

Solid nonmetals are brittle

Metalloids are elements that have properties that are similar to both metals and nonmetals. The behavior of metalloids is dependent

on the conditions that they are exposed to.

The boiling points, melting points, and densities of the metalloids vary widely.

, possesses a metallic luster, yet it is an inefficient conductor and is brittle.

The reactivity of the metalloids depends on the element with which they are reacting.For example, acts as a nonmetal when

reacting with sodium yet as a metal when reacting with

fluorine.The intermediate (in between) conductivity of

metalloids means they tend to make good semiconductors.

Most elements are __________.List 3 properties of each, metals, non-metals and

metalloids.Give three examples of each, metals, non-metals

and metalloids.(Not in the presentation)If they are generally poor conductors, they are

members of which group?Are all metals solids at room temperature?

Explain.Identify the properties of each of the following:

Niobium(Nb), Palladium(Pd), Krypton(Kr), Fluorine(F), Silicon(Si)

The color of the element symbol gives information on the physical state of the element at room temperature.

Black = solid @ room temp Red = Liquid@ room tempBlue = Gas @ room temp

Elements printed in black, red or blue are found in nature.

Those printed in 0utline0utline are not found in nature

Squares in the Periodic TableBackground colors are used to distinguish

groups of elements.

We now know that there are 3 major classes of elements: __________, __________, ____________.

We also know that there are 8 groups of elements: __________, _________, ___________, __________, __________, _________, ___________, ___________.

We know that the color of the element symbols can communicate something to us, like;

We know that the background colors can also tell us something, like;

Work in pairs around your table.(2 people)Have one person get a computer While the other gets 2 copies of the handout

with instructions.Read through all of the instructions before

beginning the activity.Collect all of the data and record it on your

sheet.You will be given 2 class periods to complete the

activity, but it will take that long so do not waste time!

Trends in Atomic SizeGroup Trends in Atomic Size

As one moves down a group the size of the atom’s atomic radius increases.

Periodic Trends in Atomic SizeAtomic size decreases across a period from left

to right.

IonsAn ion is an atom or group of atoms that

have a positive or a negative charge.Ions form when electrons are transferred

between atoms.An ion with a positive charge is called a

cation.Metallic elements form cations by loosing

one or more electronsAn ion with a negative charge is called an

anion.Nonmetallic elements form anions by

gaining one or more electrons

Trends in Ionization EnergyIonization energy is the energy required

to remove an electron from an atom in its gaseous state.First ionization energy tends to

decrease from top to bottom in a group and increase from left to right across a period. The energy required to remove the

first electron is called the first ionization energy.

Trends in Ionic SizeCations ( pos. change) are always smaller

than the atoms from which they form.Anions ( neg. charge) are always larger than

the atoms from which they form.This change in atomic size is due to the

change in the force of attraction between the protons and between the electrons.

Spread out

Trends in ElectronegativityElectronegativity is the ability of an atom

of an element to attract electrons when an element is in a compound.

In general, Electronegativity values decrease from top to bottom within a group.For representative elements ( s- and p-

block elements), the values tend to increase from left o right across a period.

Electron Configurations in GroupsElements can be sorted into

noble gases, representative elements, transition metals, or inner transition metals based on their electron

configurations.

Electron Configurations in GroupsThe Noble Gasses (Group 8 A)

The noble gasses are non metals whose s and p sublevels of the highest occupied energy level are filled

These gasses are also called the inert gasses because they rarely take part in chemical reactions.

Electron Configuration in GroupsThe representative elements

occupy groups 1A through 7A in the periodic table. The representative elements

display a wide range of physical and chemical properties.

The s and p sublevels of the highest occupied energy level are not filled.

The group number equals the number of electrons in the highest occupied energy level

Electron Configuration in GroupsThe transition elements in the B groups

separate the A groups. The transition metals are one of the B

Group elements in which the highest occupied s sublevel and a nearby d sublevel generally contain elections

The inner transition metals are B Group element which have f orbitals that are occupied by electrons. These elements are sometimes called

the rare-earth elements