Introducing “The Atom”

The smallest unit of matter that still retains the properties of an element. Atoms are so small that it would take ~1 million of them to stretch across this (.) The Atom

What three subatomic particles make up atoms?

How do I determine atomic structure?

Isotopes of Carbon

Isotopes

Radioactive Isotope: Helpful or Harmful?

The Atom: Electrically Neutral

Electron Arrangement Determines Chemical Properties of an Atom

Elements can combine to form compounds

Bonding: Share, Donate, or Receive

Ionic Bonds: Donate/Receive

Ionic Bonds

Covalent Bonds

Unequal Electron Sharing Creates Polar Molecules

Unequal Electron Sharing Creates Polar Molecules

Hydrogen Bonds are Weak Bonds Important in Chemistry of Life

Hydrogen bonds make liquid water cohesive, adhesive, & relate to surface tension

Cohesion The tendency of molecules to stick together is much stronger for water than most liquids. Trees depend on cohesion to help transport water and nutrients from roots to their leaves. Evaporation of water from a leave exerts a pulling force on water within the veins of the leaf. Surface Tension: measure of how difficult it is to stretch or break the surface of a liquid.

Water’s Hydrogen Bonds Moderate Temperature Water resists temperature change. Stabilizes ocean temps, creating favorable environment for marine life. 66% of your body weight is water; helps moderate your internal temperature. Evaporative Cooling

Evaporation = Cooling Process

Ice is less dense than liquid water As water freezes, each molecule forms stable hydrogen bonds with four neighbors, creating a 3D crystal. Ice crystal has fewer molecules than an equal volume of water. Less dense floats! Creates a blanket that prevents aquatic life forms from freezing during winter months. Polar bears use frozen surface as a hunting ground!

Water is Solvent of Life

The Chemistry of Life is Sensitive to Acidic and Basic Conditions