The Three Primary Subatomic Particles...

Protons (positive) Neutrons (neutral) Electrons (negative)

Note: protons and neutrons are made up of even smaller particles called Quarks

# of protons = the atomic number Atomic number = # of protons # of protons determines which

element it is! Who is element # 15? How many protons does lithium have? What is the atomic number of tin?

50

Phosphorus3

Number of neutrons can vary, even for the same element.

Neutrons affect the atomic mass Isotopes

same # of protons (same element) different # of neutrons (isotope)

Elements can have many different isotopes Carbon-12, Carbon-13, Carbon-14, Uranium-235, Uranium-238

Neutrons contribute to the “Strong Force” that holds the nucleus together.

Sum of the protons and neutrons

Electrons are not included Too small (1/2000)

What is the atomic mass of this atom?

A neutral atom has no charge.

positive charges = negative charges.

A neutral atom has the same # of electrons as protons

How many electrons does this atom have?

Atomic Number

Protons + Neutrons

Atomic Mass

#Protons

Element Symbol

# Neutrons = Atomic Mass – Atomic Number

Find the number of protons, neutrons and electrons in the following elements

Cl3517 Am243

95

Cl3517

17 protons17 electrons35-17 = 18 neutrons

95 protons95 electrons243-95 = 148 neutrons

Am24395

If an atom is not neutral, then it has a charge.

Ion Charged particle

This atom has: 3 protons (++

+) 2 electrons (- -) Net charge is +1 and

it is written as Li+1

It is called a Cation

If an atom is not neutral, then it has a charge.

Ion Charged particle

This atom has: 9 protons (++++++++

+) 10 electrons (- - - - - - - - -

-) It is written as F-1

It is called an Anion

How many protons? How many neutrons? How many electrons (if the atom is

neutral?)

How many protons?– The atomic number

How many neutrons?– Atomic mass minus atomic number

How many electrons (if the atom is neutral?)– Same as # of protons

Ion: Anion: Cation: Isotope:

Atomic number: Atomic mass:

Charged Particle

Same # of Protons, Different # of Neutrons.

# of ProtonsProtons + Neutrons

Negatively Charged Particle

Positively Charged Particle

Just like members of a family, certain elements of the periodic table share similarities. Like good looks!

Families of elements are groups of elements that have similar properties.

Groups can be a single column or a whole section of the periodic table.

Let’s start with the big groups first.

Similar metals are grouped together.

Two groups of metals are located on the left side of your periodic table.

Some are located on the right side of the table left of the stair steps. Most are located in the middle of the periodic table.

The elements that are usually poor conductors of heat and electricity.

First notice the location of nonmetals.

Second notice what these elements are.

The elements that are intermediate conductors of heat and electricity. (can do it but only under certain conditions)

Sometimes called Metalloids Found by the “stair-step” divider

between metals and non-metals

Specific groups that have similar properties are in the columns on the periodic table.

These are the numbers 1-18 or 1A -8A across the top of the table.

The highly reactive metallic elements located in Group 1 of the periodic table.

Tend to lose 1 electron

They are Cations (+1 charge)

React with water

sodium and potassium Brainiac

Alkali Metals are located on the left edge of the periodic table

The reactive metallic elements located in Group 2 of the periodic table.

Tend to lose 2 electrons

They are Cations (+2 charge) Do not react with

water.

Lumps of Calcium

The alkaline-earth metals make up the second column of elements from the left edge of the periodic table.

These are metallic elements in Group 3-12 of your periodic table.

They are “transition metals” because they shift from being similar to group 2 (alkali metals) over to being like group 13 moving left to right.

The highly reactive elements located in Group 17 of the Periodic table.

Are all diatomic(F2, Cl2, Br2, I2) Atoms Tend to gain 1 electron They are Anions (-1 charge)

HalogenLamps

Bromineburning

The halogens are in the second column from the right of the periodic table.

No not kings and queens. The unreactive gaseous elements

located on Group 18 of the periodic table.

Noble gases are located on right edge of the periodic table.

And on the throne when kings and queens fart !

Diatomic = two atoms There are 7 diatomic atoms N2, O2, F2, Cl2, Br2, I2, H2

Remember them by the rule of “7” Starts with element 7 = Nitrogen Forms a 7 through oxygen and down to iodine The 7th diatomic element is hydrogen

Man-Made Elements• Which are the man-made or synthetic Elements?• How are synthetic elements made?

Cyclotron, protons, alpha particles and heavy atoms

• Why do scientists continue to try to make elements?