CHEM 2A: CH 1-10 Flashcards
Combination Reactions
2 Chemical species combining to become one
A+B —-> AB
Gases Behave Most Ideally at ____
low pressure and high temperature
Boyle’s Law
Relationship b/w pressure and volume
P1V1 = P2V2
Combined Gas Law
P1V1/T1 = P2V2/T2
PV = nRT
P = atm V = L n = moles R = (L)(atm)/(k)(mol) T = Kelvin
Bond Order
1/2 number of valence electrons in bonding orbitals - number of electrons in anti-bonding orbitals
Molecular Orbital Theory (MO Theory)
Molecular orbitals are a combination of atomic orbitals, delocalized around the molecule
pi-Bond
P-P interaction, perpendicular to the internuclear axis
Sigma-Bond
Where the orbitals overlap in the internuclear axis
Hybrid Orbitals
Are localized (found on a specific point on molecules)
Hybridization
Atomic orbitals (s,p,d,f) mix together to give hybrid orbitals
Ground State
Lowest energy state
Orbital
3-d probability density predicting the most likely position where electrons cam be found
Decomposition Reactions
A single reactant compound breaks down into two or more product substances
AB—-> A + B
Law of Combining Volumes
When gases at the same temperature and pressure react, the reactant and product volumes in a ratio of small whole numbers
Bohr Model of H Atom
- Electrons in orbitals of different energy around nucleaous
- Energy of electron are quantized on orbitals (not in between)
- Different energy levels hold different numbers of electrons
Reversibility
Indicated by the double arrow
————–>
Double Replacement Reactions
When solids of 2 compounds in aqueous solutions are mixed a positive ion from one species may combine with a negative ion from the other species to form a precipitate.
AX + BY ——> AY + BX
Single Replacement Reactions
One element replaces one of the ions in a compound
A + BX —–>AX + B
Neutralization Reactions
Reaction b/w acid and base (forms water and a salt)
7 Strong Acids
HNO3 (Nitric Acid) H2SO4 (Sulfuric Acid) HCl (Hydrochloric Acid) HBr (Hydrobromic Acid) HI (Hydroiodic Acid) HClPO3 (Chloric Acid) HClO4 (Perchloric Acid)
Scientific Notation
- 1 none-zero digit to the left of the decimal
- When decimal moves left, exponent increases
- When decimal moves right, exponent decreases
Chemical Properties/Changes
Properties: Flammability
Changes: Burns, Rust
Physical Properties/ Changes
- Observe with senses (height, length, width, smell, sight, size, color, boiling point)
- Changes: boil water, melt ice
- DOES NOT CHANGE SUBSTANCE
Percent Composition
%A = Parts A/Total Parts X 100
Isotopes
Two or more atoms of the same element that have different masses (different number of neutrons)
Dalton Atomic Theory
1) Each element is made up of individual atoms
2) Atoms are indivisible
3) All atoms of one element in every respect
4) Atoms of one element are different from atoms of any other element
5) Atoms combine to form compounds
Law of Definite (or constant) Composition
Compound always made up in same proportion by mass
Significant Figures
1) All non-zero digits are significant
2) All zeros b/w non-zero digits are significant
3) All zeros to the left of the 1st non-zero digit are NOT significant
4) Zeros to the right of the las non-zero digit when there is a decimal
5) Zeros to the right of the last non-zero digit are not significant if NO decimal
Metric Prefixes
Kilo- 1,000 Hecta- 100 Deca- 10 Meter- 1 Deci- 0.1 Centi- 0.01 Mili- 0.001
Ionic Bonds
Chemical bonds arising from the attractive forces b/w oppositely changed ions (interaction b/w cation and anion)
- Strong
- Solid @ room temperature
- Crystal Lattice
Covalent Bonds
Chemical bond b/w 2 or more atoms that share a pair of electrons
- Permanent until broken by chemical change
- nonmetals interacting w/nonmetals
Cations VS. Anions
Cations- positive ions
Anions- negative ions
Temperature Conversions (F, C, K)
TC= (5/9)(TF-32) OK= -273.15 degrees C TK= TC + 273
Limiting Reactants
Reactant that is totally consumed first, determines maximum yield possible
Solids
- Stays same shape
- Particles locked into place
- Little free space b/w
Liquids
- Volume remains constant
- Shape changes
- Particles move/slide past each other
- Little free space b/w
Gases
- Volume is variable
- Move freely @ high speeds
- Well seperated
- Assumes shape of container
Particulate Matter
Smaller than microscopic atoms, H2O molecules, protein molecules
Microscopic Matter
Microscope, animal cells, plant cells
Macroscopic Matter
Matter= anything that has mass and takes up space
see w/eyes
Metric Units of Mass, Length, Volume
Mass= Kg Length= m Volume= m^3
Polar VS. Non-polar Covalent Bonds
Polar Bonds- 2 atoms form a molecule using a covalent bond, shape electrons dipole-dipole, unequal share ionic charge
Non-Polar Bonds- equal share of electrons, no ionic charge
Ground VS. Excited State
Ground- the energy level an electron normally occupies
Excited - Release energy to go back to ground state
Electron
- Negative Charge
- 1/1837 mass H
- e-
STP
273 K
1 atm
Percent Yield
Actual Yield/Ideal Yield X 100
Determining Molecular Formula
1) Determine Empirical Formula
2) Calculate molar mass of the Empirical Formula Unit
3) Determine molar mass of the compound
4) Divide MM of compound by MM E.F. (n)
5) Multiply by empirical formula