1 Matter, Mass, Molecules, Moles, & Motion

Atomic mass unit (AMU) designation of weight 1 AMU = 1 / (6.02 x 10^23) g/mol 1 Mol = 6.02 x 10^23 1 AMU element = grams when 1 Mol present 1 Mol Carbon = 12g

Add atomic mass of all elements present in molecule C6H12O6 = (6x12) + (1x12) + (16x6) = 180g

Number of protons in the nucleus of an atom Does not change - would change the element Hydrogen 1 proton (+) Calcium 20 protons (+)

Total number protons and neutrons in the nucleus Nitrogen 14.007 7+ protons 7 neutrons (neutral)

Same element (# protons) w/ different number neutrons Different atomic mass Nitrogen-15 7+ protons 8 neutrons Atomic mass = 14.007

Universal solvent d/t dipole nature Less dense when frozen - ice floats Amphoteric - acid & base High latent heat - stores more heat per unit volume than other substances and releases heat slowly High vaporization heat - large amount heat required to break hydrogen bonds and the heat carried off as H2O vapor Cohesive (molecules tend to stick together) AND adhesive (tend to stick to surfaces w/ polar groups) Dissociates into H+ & OH¯ Attraction & repulsion forces among H2O molecules - produces space between for gas molecules HIGH ↑BP ↑MP

Smallest fraction of an element w/ element characteristics “Building block” Composed of subatomic particles - protons, neutrons, electrons

Substance that cannot be separated into simple substance C, O, & N Oxygen exists as diatomic element (O2)

Two or more atoms chemically joined together H2, N2, O2 Same elements Exist in nature bound to self

Molecule that contains at least 2 different elements C6H12O6 (glucose)

State of matter Solid - less energy, densely packed, slowest Liquid - more energy, less dense, faster Gas - most energy, moving & dispersing, fastest

Change in matter composition Bonds broken & new bonds formed → new chemical entity produced w/ different properties/reaction CO2 + H2O → H+ + HCO3

Attraction b/w all objects and force r/t Smaller distance = ↑ force 1 / d^2

Gravitational force experienced by body (mass) on earth Relative to gravitational force applied to mass

Unchanged ↑ mass ↑ gravity reaction ↑ weight

Interaction b/w unlike molecules H2O molecules attract to the glass Pulling down & raising up along sides CONCAVE

Interaction b/w like molecules Exhibit mutual attraction force ↑ distance ↓ force CONVEX Liquid pulls away from glass towards other H2O molecules

1st shell 2e¯ 2nd & 3rd shell 8e¯ Molecules react w/ other molecules to fill outer (valence) shell and become more stable

Shared e¯ pair b/w 2 atoms Overlap orbitals or e¯ clouds to satisfy octet therefore more stable Equal = non-polar Unequal = polar

D = M / V 1Mol = 22.4L Gram molecular weight or mole Liquids measured in grams/cm^3 (cm^3 = mL) Gas/vapors: MW/GMV or g/L

Equal volume gas at STP have same number molecules 1Mol = 6.02 x 10^23 molecules

Liquid or gas weight of unit volume Compared to standard volume H2O or dry air Ratio b/w two densities Liquid MW / H2O MW Gas MW / Dry air MW ↓specific gravity = lower density ↓resistance

Extremely reactive d/t out shell not filled 7e¯ valence Highly electronegative Form salts w/ Na+ Acids when combined w/ H+ F, Cl, Br, I

Universal solvent d/t dipole & polar properties Able to dissolve polar substances High melting & boiling point Less dense when frozen than in solid state (ice floats) Amphoteric - acid & base properties Water dissociates into H+ & OH¯ (contributes to acid/base balance) Tetrahedral shape to maximize distance b/w e¯ pairs Attractive and repulsive forces among H2O molecules - makes space b/w molecules for gas High latent heat - stores more heat per unit volume & releases heat slowly High vaporization heat - large amount heat required to break hydrogen bonds & heat carried off as vapor Cohesive AND adhesive