Chemistry of Lifechapter 2

Chemistry of Lifechapter 2

•Atoms - the basic unit of matter

•Made up of 3 parts

Atomic structureAtomic structure

• Protons (+) charge

• Neutron (0) charge

• Electrons (-) charge

ElementElement

• A pure substance that consist only one type of atom

• EX: C,H,O,N

ISOTOPESISOTOPES

• Atoms of the same element that have different # of neutrons

28

Ni

Nickel

58.71

1. Atomic #

2. Element symbol

3. Name of atom

4. Average atomic mass

CompoundCompound

• A substance formed when two or more elements combine in a definite proportions

Figuring out atomic structureFiguring out atomic structure

How many protons, electrons, & neutrons does carbon have?

CarbonCarbon

• Atomic number = 6

• Carbon will have 6 protons & 6 electrons

• Atomic mass = 12• (round atomic number to a whole #)

• To calculate # of neutrons:

• Atomic mass 12• - atomic # - 6• = neutron # 6

Lets try one moreLets try one more

• Find the # of protons,

electrons, & neutrons

for chlorine

• Chlorine:• Atomic # is 17,• It has 17 protons & 17

electrons

• Atomic mass 35• Atomic # -17

neutron # = 18

Molecules and BondingMolecules and Bonding

• more ways to view molecules

Chemical BONDS!Chemical BONDS!

• Chemical Bonds: Are the electrical forces linking atoms.

Molecules and BondingMolecules and Bonding

Two Types!

•Covalent Bonds: Are characterized by the sharing of pairs of electrons between atoms.

Molecules and BondingMolecules and Bonding

Two Types!

•Ionic Bonds: Are characterized by the Stealing or Giving of electrons between atoms.

Molecules and BondingMolecules and Bonding

Molecules and BondingMolecules and Bonding

• How many bonds can an element make?

Count the bonds for Carbon!

Properties of WaterProperties of Water

• Water is a Polar Molecule

• Uneven Electrical Charge

Properties of WaterProperties of Water

• Water is essential for life!!!

• 78% of the body is made up water

• It is the universal solvent

• The body’s chemical reactions require water!