Periodic table
The number of protons in an atom. This # determines the identity of an element.
What is atomic number?
A theory to predict the shape of molecules
What is VESPR theory?
Changes that alter only the state or appearance, but not the composition of a substance (atoms or molecules do not change their identity)
What are Physical Changes?
A reaction that gives off energy
What is an exothermic reaction?
1 mole of any substance contains 6.02 x 1023 molecules
What is Avagadro's number?
Very reactive non-metals in group 7A of the periodic table
What are halogens?
A bond resulting when two atoms share electrons, lowering their potential energy in accordance with Coulomb's Law so the electrons can be close to both nuclei at the same time
What is a Covalent bond?
Formed when single protons (H+) normally associate with water molecules
What is the Hydronium ion?
This states that energy can be neither created or destroyed
What is the Law of Conservation of Energy? (or What is the 1st Law of Thermodynamics?)
A chemical formula reduced to lowest terms
What is an empirical formula?
The energy needed to remove an electron from an atom
What is Ionization energy?
An atomic symbol surrounded by valence electrons represented as dots
What is a Lewis structure?
The number (or "charge") given to each atom in a compound if all of the shared electrons were assigned to the atom with greatest electronegativity.
What is the Oxidation Number?
The type of energy associated with the motion of an object
What is Kinetic Energy?
Found by simply summing the atomic masses (on the periodic table) of each atom in a chemical formula.
What is Formula or molecular mass?
As atoms or ions get larger, the electron being removed is farther from the nucleus… the attractions are less… the energy needed is less… the ionization energy is less.
What are Ionization Energy trends?
Bond between two atoms with significantly different electronegativities, resulting in partial + and – charges
What is a Polar bond?
The reaction of a fuel with O2, which forms CO2 and H2O as products
What is a Combustion Reaction?
The amount of heat required to raise the temperature of 1 mole of a substance by 1oC.
What is the Molar Heat Capacity?
(Actual Yield/Theoretical Yield) x 100
What is percent yield?
Properties repeat periodically if you arrange elements by atomic mass.
What is the Periodic Law?
Two or more Lewis structures that have the same skeletal formula, but different electron dot arrangements
What are Resonance Structures?
An equation with spectator ions removed
What is a net ionic equation?
A thermodynamic function related to the enthalpy and entropy of a chemical system
What is Gibbs Free Energy?
Changing the coefficients in front of chemical formulas to ensure the number of atoms on the left side are equal to the number of atoms on the right side of a chemical equation
What is a Balanced Equation?