Atomic Structure and Identification

Think about it…

What is the difference between matter, atoms and elements???

Everything is made of matter!!!!!!!!

An atom is the smallest particle of an element

An element is something that cant be broken down into simpler substances.

What is this?!??!

Electron Configuration

What does an atom look like?!?!

Structure of Atoms

All matter is made up of many atoms

Atoms are made of subatomic particles:

Protons

Neutrons

Electrons

Each of these subatomic particles has its own charge, location in the atom, and mass

Structure of Atoms

Proton Neutron Electron

Location Inside the nucleus

Inside the nucleus

Space outsidethe nucleus

Charge Positive (+) Neutral (no charge)

Negative (-)

Identifying Atoms

Atomic Number

Identifying Atoms

We use atomic numbers to organize elements on the periodic table

Atomic number increases from left to right

The atomic number tells you the number of protons in an atom

All elemental atoms have the same number of protons and electrons!

Practice!!!!

What atom has 22 protons?

A. Ti

B. Zr

C. He

D. O

Practice!!!

How many protons does Sulfur (S) have?

A. 15

B. 16

C. 17

D. 18

Practice!!!

The atom with the atomic number of 53 is ______.

A. Sn

B. Sb

C. Te

D. I

Identifying Atoms

Atomic Mass

Identifying Atoms

Atomic mass (aka atomic weight) is the sum of the protons and neutrons in the nucleus of that atom

How many protons and neutrons does Carbon have??

6 protons

12 – 6 = 6

6 neutrons

Number of Neutrons = Atomic Mass – Atomic number

Identifying Atoms

Sometimes, atoms of the same element have different atomic masses! These are called isotopes

These atoms are all isotopes of each other. They have the same number of protons but different number of neutrons. They are STILL Li atoms!

Atomic Mass

Atomic #

Practice!!!

How many neutrons does Argon (Ar) have??

A. 17

B. 18

C. 22

D. 40

Practice!!!

What is the atomic mass of Magnesium (Mg)?

A. 11

B. 12

C. 23

D. 24

Practice!!!

How many electrons does Phosphorus (P) have?

A. 15

B. 30

C. 46

D. 106

Pure Substance

A pure substance is matter that always has exactly the same composition

A pure substance has a fixed, uniform composition.

Two categories of substances: elements and compounds

Closer look at Elements!

Elements in Earth’s Atmosphere

Elements

It cannot be broken down into a smaller substance!

If it is on the periodic table…its an element!

No two elements contain the same type of atoms

Compound

What is a compound????

A compound is made from two or more different elements that are bonded together

Molecule

A molecule is formed when two or more atoms join together

Mixture

Mixtures retain some of the properties of their individual substances.

No matter how well you stir the salsa, the ingredients will not be evenly distributed. More onions in one bite.

Two types of mixtures

Heterogeneous Mixture

In a heterogeneous mixture, the parts of the mixture are noticeably different from one another

Homogeneous Mixtures

In a homogeneous mixture, the substances are so evenly distributed that it is difficult to distinguish one substance in the mixture from another

Solution

Solutions are groups of molecules that are mixed up in an even distribution.

They are like homogenous mixtures.

Think about sugar in water and sand in water.