1. Atomic Structure

2. Housekeeping… Need Music Requests for your test or you get my choice
Need a gatekeeper for each class
Definition of explode - a violent release of energy resulting from a rapid chemical or nuclear reaction, esp one that produces a shock wave, loud noise, heat, and light.

3. Objectives:
Determine how many of each subatomic particle are in an atom
Use an element tag to determine subatomic particles in atoms

4. Matter and Atoms
Matter describes everything that has mass and takes up space
What is not matter?
Black holes have mass, but don’t take up space
Antimatter has mass, it just has an opposite spin to its counterpart

5. Atoms and Elements An atom is the smallest unit of matter
An element is the simplest form of a substance that cannot be broken down by chemical means
What is the difference?

6. What is a subatomic particle?
Subatomic means “smaller than an atom”
The three subatomic particles are
Protons
Neutrons
electrons

7. Locations
Subatomic particles are either inside the nucleus, or outside of it
Outside of the nucleus is referred to the electron cloud, where the electrons are found
The protons and neutrons are found inside the nucleus

8. The electron cloud
Electrons move around the nucleus and have different energy levels
Electrons have less energy the closer they are to the nucleus

9. Modern model
Shows an electron cloud rather than individual electrons outside of the nucleus
Denser areas of the cloud mean a higher probability of electrons

10. Energy in the cloud
Each energy level can hold a certain number of electrons
each shell but the first will fill to 8 before a new shell is made
8 is great!!!
1st shell – 2
2nd shell – 8
3rd shell - 18

11. Electrical Charge Electrical charges can be positive or negative
Protons are positively charged
Electrons are negatively charged
Neutrons have no electrical charge, they are referred to as neutral

12. Electrical Charges ctd.
An atom usually has an equal number of positively charged protons and negatively charged electrons
This makes an atom electrically neutral

13. Atomic number
The atomic number is the large number within the element tag on the periodic table
The atomic number tells you how many protons are in one atom of that element
Protons determine an element’s identity
So, in a neutral atom, the atomic number tells you how many protons and electrons are in an atom - APE

14. Mass Number
The more protons and neutrons an atom has, the greater its mass
The total number of protons and neutrons in an atom is called its mass number
Electrons are left out of the calculation of the mass number because they add so little mass to an atom

15. Average atomic mass
Most atoms exist in a number of different forms, called isotopes
Each form has the same number of protons, but a different number of neutrons
Isotopes have different physical properties but their chemical properties are the same

16. Determining numbers of neutrons
The average atomic mass of the elements are found as a decimal number on the periodic table
This number can be rounded to a whole number, then you subtract the atomic number (number of protons) and you are left with the neutrons of the atom – M-A=N