1. What did you like/dislike about Unit 1
Bell ringer
What did you like/dislike about Unit 1
List your knowledge on basic chemistry
Biochemistry – unit 2

2. Basic Chemistry
Objectives: Define matter, atom, element, and compound Recognize and know the charge and location of a proton, neutron, and electron Utilize the periodic table To understand the shape of atoms and be able to draw them Calculate atomic mass and number of subatomic particles

3. Unit 2: Biochemistry – ATOMS!
The Nature of Matter!

4. The Basics Matter: anything that has mass and takes up space.
Atom: The basic unit of matter
Element: A pure substance that consists of entirely one atom.
Compound: a substance formed by the chemical combination of two or more elements.
The Basics

5. Proton: (+) Positively charged particle in the nucleus of the atom.
Neutron: (0) A particle in the nucleus that has no charge.
Strong forces bond the protons and neutrons together to form a nucleus in the center of the atom.
Electron: (-) negatively charged particle that is in constant motion outside the nucleus (in the electron shell).
Subatomic particles

6. Sub-Atomic Math Sub-Atomic Particle Mass Charge Proton 1 +1 Neutron
Electron -1

7. The Atom Helium Atomic Number 2 Element Symbol He Helium 4
Element Name
Atomic Mass

8. I spent my time arranging the elements and came up with the
Each element is made of atoms. The elements are currently arranged by atomic number.
I spent my time arranging the elements and came up with the
Periodic Table of Elements in 1865.
Mendeleev

9. = number of protons + number of neutrons
You can determine the number of protons, neutrons, and electrons using the Periodic table.
= number of protons + number of neutrons
= number of protons
= number of electrons 6 C
Carbon 12
Atomic Number
Element Symbol
Element Name
Atomic Mass

10. Helium has two protons, two electrons, two neutrons
Let’s Try It!
The Atom Helium
Atomic Number
Protons= 2 2 He
Helium 4
Electrons= 2
Element Symbol
Element Name
Neutrons= 4
- 2
= 2
Helium has two protons, two electrons, two neutrons
Atomic Mass

11. Shell contains Electrons
The Atom Helium
Shell contains Electrons
Nucleus : Contains Protons and Neutrons e He
P:2
N:2 e

12. Electron Shell : Energy Levels
Energy Levels: in electron cloud
1st Energy Level = Max. of 2 electrons
2nd Energy Level = Max. of 8 electrons
3rd Energy Level = Max. of 8 electrons
Electron in 1st energy level
Electron in 2nd energy level
Electron in 3rd energy level
Nucleus

13. Valence Electrons
Valence electrons: electrons in the outer most energy level
= valence electrons- 8 red dots in outer energy level

14. BOHR’S MODEL e e e
P:5
N:6 B
Niels Bohr e e
Bohr Model

15. Drawing an atom model… B
Begin with the element and determine how many protons, neutrons, and electrons there are.
Boron: Atomic Number 5
Atomic Mass 11
Protons: 5
Neutrons: 6
Electrons: 5
P:5
N:6 B
go inside nucleus
go in electron shell

16. Boron B The Nucleus contains 5 protons and 6 neutrons
There are two electrons on the first energy level. This energy level is full, so we go to the next energy level
P:5
N:6 B
After placing 2 electrons on the first energy level, Boron still has 3 more electrons. These electrons are put on the 2nd energy level.
Valence Electrons: There are 3 valence electrons. To determine this, we look at the outer most energy level (in this case the 2nd level). Then we count the number of electrons. There are 3 electrons on the 2nd energy level.
Boron

17. REMEMBER…
ALWAYS FILL THE INNER ENERGY LEVELS FIRST!!! START WITH THE 1ST ENERGY LEVEL!

18. Draw an atom of… Sodium: Na Atomic #: 11 Atomic Mass: 23 Na Determine…
Protons ( + ) =
Neutrons ( 0 ) =
Electrons ( - ) = 11 12
P:11
N:12 Na
Valence Electrons? = 1

19. Draw an atom of… Beryllium: Be Atomic #: 4 Atomic Mass: 9 Be
Determine…
Protons ( + ) =
Neutrons ( 0 ) =
Electrons ( - ) = 4 5
P:4
N:5 Be
Valence Electrons? = 2

20. Draw an atom of… Neon: Ne Atomic #: 10 Atomic Mass: 20 Ne Determine…
Protons ( + ) =
Neutrons ( 0 ) =
Electrons ( - ) =
P:10
N:10 Ne 10
Valence Electrons? = 8
NEON IS A STABLE ELEMENT (OR UNREACTIVE) BECAUSE IT’S OUTER ENERGY LEVEL IS FULL!!!

21. Practice Worksheet # 1 Drawing atoms Due today
Worksheet # 2 Chemical basis of life Due today
PERIODIC TABLE sheet… Color code it
Practice