1. Basic Chemistry

2. What is Matter?
Matter – the substance of which any physical object is composed
States of Matter:
Solid
Liquid
Gas
Controlling factors:
Temperature
Pressure
Examples: Gold Mercury Oxygen
solid liquid gas

3. The stuff that makes up all matter
The make-up of solid matter on Earth:
Atoms  Elements  Compounds  Minerals  Rocks
(smallest) (largest)

4. Element: Periodic Table Fundamental building block
Smallest matter that can’t be broken down
Periodic Table
Rows=periods
Columns=groups; elements of a group have similar properties
Non-metals, metals, and metalloids

5. Periodic Table of Elements

6. Atomic Structure Atoms: Stuff that builds elements
Atoms  Elements  Compounds  Minerals  Rocks
(smallest) (largest)
Atoms:
Stuff that builds elements
Smallest particle that uniquely defines an element
Made of subatomic particles: protons, neutrons, electrons

7. Atomic Structure Particles that make up an atom:
Protons: positive (+) charge
Neutrons: no charge
Electrons: negative (-) charge, smallest of the subatomic particles
Protons + neutrons define the nucleus of an atom.
Layers of electrons that orbit around the nucleus are called orbitals or energy-level shells.

8. Subatomic Particles equal in a neutral atom Atomic Number
NUCLEUS
ELECTRONS
equal in a neutral atom
PROTONS
NEUTRONS
NEGATIVE CHARGE
Atomic Number
equals the # of...
POSITIVE CHARGE
NEUTRAL CHARGE
Most of the atom’s mass.

9. Atomic Structure

10. Periodic Table of Elements
Atomic Number (# of protons)
Mass number = # protons + # neutrons
YES
These are called isotopes.
Example: (Carbon) 12C 13C 14C
Can atoms of the same element have different mass numbers?
Atomic weight =
# protons + average # neutrons

11. Atomic Structure Atoms of the same element:
have the same number of protons (i.e., same atomic number)
can have different numbers of neutrons (referred to as isotopes)
can have different numbers of electrons
Ion – an atom that has gained or lost an electron

12. Mass # Atomic # Nuclear symbol: Hyphen notation: carbon-12 Isotopes
Atoms of the same element with different mass numbers.
Nuclear symbol:
Mass #
Atomic #
Hyphen notation: carbon-12

13. Isotopes
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14. 17 37 20 Isotopes Chlorine-37 atomic #: mass #: # of protons:
# of electrons:
# of neutrons: 17 37 20

15. Atomic Structure Sodium atom Chlorine atom loses an electron
(becomes positively
charged)
Chlorine atom
gains an electron
(becomes negatively
charged)

16. Atomic Structure: IONS
Ion: atom that has gained or lost an electron
Types of IONS:
CATIONS – a loss of electrons, resulting in a positive (+) charge
ANIONS – a gain of electrons, resulting in a negative (-) charge
Examples: Na+ (cation) Cl – (anion)
NaCl (table salt)
chemical compound

17. Compounds Definition: Examples: NaCl H2O
Atoms  Elements  Compounds  Minerals  Rocks
(smallest) (largest)
Definition:
A chemical compound consists of elements that combine in a specific ratio.
Examples: NaCl H2O
The smallest quantity of a compound is called a molecule.
Molecules are held together by chemical bonding.

18. What is a chemical bond?
An attractive force between the nuclei and valence electrons of different atoms that binds them together
Formation of a compound by combining two or more elements
Manner in which electrons are distributed
In bonded atoms, electrons may be lost, gained, or shared
Bonds form in order to…
decrease potential energy (PE)
increase stability

19. Ionic Bonds Ionic Bonds are formed by the TRANSFER of electrons
Moderately strong bond
What constitutes an ion?
Positive or negative charge
Cation or anion
Opposites attract
Cations will attract anions
Anions will attract cations
Bonding ALWAYS takes place in the valence shell between valence electrons

20. Ionic Bonding
Na+
Cl–

21. What makes an ionic bond?
Must include a metal + a non-metal
Metal = cation
Non metal = anion
Anion “takes” electron from cation
Cation is willing to give it away, to lower an energy level
Anion is looking to fulfill the octet rule
For this reason – group I and II metals “LOVE” group 17 non-metals (halogens)
Creates a salt

22. Covalent Bonds Compounds that are made of molecules
Bonds that are formed by SHARING electrons
Electrons are shared from the valence shell, still want it full!
Generally STRONGEST Bonds
Non-metal + non-metal (diamond, pure C)

23. What makes a Covalent Bond
Non-metal + non-metal
Some examples below
Can share more than one pair of electrons
single bond shares one pair electrons
double bond shares two pairs electrons
triple bond shares three pairs electrons

24. Metallic Bonds Metal + metal
Generally weaker, less common than other bonds
Electrons drift around from atom to atom
Electrons are free to move from atom to atom
This is why they are good conductors of electricity
Gold, copper, silver

25. Van der Waals Van der Waals bonding:
sheets of covalently bonded atoms held together by weak electrostatic forces
very weak bonds
examples: graphite, mica

26. Van der Waals  metallic  ionic  covalent
Bond Strength
Van der Waals  metallic  ionic  covalent
(weakest) (strongest)