2 main types of Chemical Bonds:
1. Ionic Bond: attraction of a positively charged ion to a negatively charged ion. Atoms can gain or lose electrons to become charged ions.
Because of this opposite attraction, ionic bonds are strong. lonically bonded atoms create ionic compounds.
Ex: Table salt, sodium chloride,( NaCl) —attraction between positive sodium ion( Na+) a negative chloride( Cl-)
2. Covalent Bond: forms when 2 atoms overlap their outer energy levels in order to share valence elections. The shared electrons are attracted to the nuclei of both atoms. Covalent compounds are also called molecules.
is formed by covalent bandes
Bonding in Water:
The charged ends of one water molecule are attracted to the opposite charged regions of its neighboring water molecules. This is Hydrogen Bonding.
Main properties of Water:
1. Cohesion: an attraction of the same particles; Water is a polar molecule w/ a slightly negative and positive end. The negative end attracts the positive end of the water molecules. Due to this, water molecules act like tiny magnets and cling.
2. Adhesion: attraction of water to a different substance. The polarity of water attracts many different substances.
Ex: water in a narrow tube: water's surface is higher than the center as it adheres to the surface of the tube.
3. Surface Tension: A measure of how different it is to stretch/ break the surface of a liquid. Hydrogen bonding in water molecules gives it a strong surface tension. Hydrogen bonds pull from the sides + bottom, but not the top. This uneven bonding pulls surface molecules down and closer.
—Surface Tension almost forms a thin, invisible film on the water's surface.
4. Capillary Action: Movement of water through a narrow tube. Occurs when forces of cohesion, adhesion, and surface tension work together. (Ex: water movement through a plant).
Expands when Freezes: