Chapter 2 Flashcards
(26 cards)
Life is carried of through chains of _______
Chemical Reactions
Nucleus
Made up of protons and neutrons, very small compared to the entire atom
Protons
Positive Charge, Mass
Neutrons
No charge, mass
Electrons
Orbit Nucleus, negatively charged, negligible mass
Atomic Number
Number of protons
Element
Cannot be reduced into anything simpler
Mass number
protons + nuetrons
Isotopes
Different forms of the same element, may have different mass because the number of neutrons differ
Half life of C-14
5600 years
Molecules
Two or more atoms combined
Stability
Full outer electron shell
Covalent bonds
Two atoms without full outer shells may share electrons. (example: water)
Nonpolar covalent bonds
H2 neither nucleus exerts more attractive pull on shared electrons
Polar covalent bonds
H2O. Oxygen has greater atomic number than hydrogen thus attracts the shared the electrons more
Ionic Bonds
When electrons are lost or gained, one atom has much greater electronegativity
Ions
Charged atoms, loses equals positive charge, gains equals negative charge
Ionic compounds
Ions electrostatic attraction to each other, Positive/negative attraction
Hydrogen bonds
Example: Water solution. Polar covalent bonds.
Density
How many molecules per unit volume. Ice
Specific Heat
Takes large amount of energy to raise of water
Hydrophobic
Molecules do not readily form bonds with water
Hydrophilic
dissolve in water. Bonds with water.
Acid
Yields hydrogen ions, adds them to solution
