Chapter 2 : The Chemical Basis of Life (part 2) Flashcards
Example of a compound
Sodium chloride (table salt)
Ionic bond
When atoms can obtain a stable number of electrons by giving up or gaining electrons forming
-formed between elements on the same side of the periodic table
Covalent bond
Form when 2 or more elements share electrons to become stable
- stronger than ionic bonds
- Formed bwtn the same or similar elements
Molecule
Stable compound formed by covalent bonding
Ion
An atom or molecule with an electrical charge resulting from gain or loss of electrons
What happens to an ion’s charge when an electron is gained or lost
Lost - a positive charge results
Gained - Negative charge results
Ionic bond
When ions with opposite charges attract each other and stay held together
Agarose gel electrophoresis
Laboratory method that separates molecule based upon charge, size, and shape
Covalent bond
When molecules in a bond continue to compete for shared electrons
Electronegativity
The attraction for shared electrons
Nonpolar covalent bonds
When the pull toward each atom is equal in an element
Hydrogen bond
The charged regions on molecules are electrically attracted to oppositely charged regions on neighboring molecules
The Properties of Water
- Cohesion and Adhesion
- Surface tension
- High heat capacity
- Ice is denser than water
- Water is the solvent of life
Cohesion
The tendency of molecule of the same kind to stick together is cohesion
Adhesion
The tendency of 2 kinds of molecules to stick together is adhesion
