CHEM 103 STUDY GUIDE(VERIFIED BY EXPERTS)
UPDATED 2024|Module 1 and 2: A+ GRADED
mega M 10^6 m
kilo k 10^3
centi c 10^-2
milli m 10^-3
micro μ 10^-6
nano n 10^-9
Angstrom A 10^-10
pico p 10^-12
Classification of Matter:
● Element: only one type of atom These are all pure substances!
● Atom: single, lone atom
● Molecule: multiple atoms, covalently bonded
● Compound: multiple different atoms
● Mixture: multiple different atoms and/or molecules not bonded
○ Homogenous: uniformly distributed
○ Heterogenous: not uniformly distributed
Chemical vs. Physical Change:
● Chemical Change: making/breaking different chemical bonds
○ NEW SUBSTANCES CREATED
○ Change in color, odor, sound, heat release/consumption, light release
● Physical Change: different arrangement of same molecule
○ NO NEW SUBSTANCES FORMED
○ Change in temperature, phase, size, shape
○ Phase changes
Atoms:
● Size of electron cloud=1 A
● Mass concentrated in the nucleus
● Mass of proton=mass of neutron>mass of electron
● Plum Pudding Model: like charges would repel and unlike would attract
● Rutherford’s Gold Foil Experiment:
○ If charges were dispersed, there would be no deflection
○ Protons are all clumped in the middle of the nucleus and neutrons bind the
nucleus together
○ Odds of hitting=A of nuc/A of atom
○ 1 in 2000 hit (easy to pass through because there is empty space in electron
cloud)
, Isotopes and Mass Spectrometry:
● If 2 particles have the same charge:
○ lighter=deflected more
○ heavier=deflected less
○ Angle of deflection=mass to charge ratio
● Mass Spec:
○ Hard: breaks bond while ionizing, gives elemental analysis ration
○ Soft: ionize without breaking bonds, shows masses of each molecule
■ Which is more present in a mixture
● Isotopes: atoms of the same element with a different number of neutrons
○ Same atomic number (protons)
○ Different mass number (protons plus neutrons)
○ Percent Abundance: fraction of atoms of each isotope in a natural sample of an
element
■ %= number of atoms of a given isotope/total number of atoms of all
isotopes of element
Molecular Compounds Ionic Compounds
composition non-metal metal/non-metal
nanoscale Individual molecule Ions in crystal lattice
state Gas, liquid, solid, brittle/weak, Crystalline solid, hard/brittle
soft, waxy
Melting point low high
Boiling point low high
Heat transport low low
conductivity low Low (high if molten)
Module 3:
● Atoms often form stable ions by gaining or losing electrons until they match a noble gas
electron count
● Melting points: who has the most easily overcome force
○ High charge=strong force=highest melting point
○ High separation=lower melting point
Solutions:
● A solution is a uniform mix of 2+ pure substances
● Solvent is present in greatest abundance
● solute=any other solution component
● Electrolyte: substance that breaks down in solutions
○ strong=100% break into ions
UPDATED 2024|Module 1 and 2: A+ GRADED
mega M 10^6 m
kilo k 10^3
centi c 10^-2
milli m 10^-3
micro μ 10^-6
nano n 10^-9
Angstrom A 10^-10
pico p 10^-12
Classification of Matter:
● Element: only one type of atom These are all pure substances!
● Atom: single, lone atom
● Molecule: multiple atoms, covalently bonded
● Compound: multiple different atoms
● Mixture: multiple different atoms and/or molecules not bonded
○ Homogenous: uniformly distributed
○ Heterogenous: not uniformly distributed
Chemical vs. Physical Change:
● Chemical Change: making/breaking different chemical bonds
○ NEW SUBSTANCES CREATED
○ Change in color, odor, sound, heat release/consumption, light release
● Physical Change: different arrangement of same molecule
○ NO NEW SUBSTANCES FORMED
○ Change in temperature, phase, size, shape
○ Phase changes
Atoms:
● Size of electron cloud=1 A
● Mass concentrated in the nucleus
● Mass of proton=mass of neutron>mass of electron
● Plum Pudding Model: like charges would repel and unlike would attract
● Rutherford’s Gold Foil Experiment:
○ If charges were dispersed, there would be no deflection
○ Protons are all clumped in the middle of the nucleus and neutrons bind the
nucleus together
○ Odds of hitting=A of nuc/A of atom
○ 1 in 2000 hit (easy to pass through because there is empty space in electron
cloud)
, Isotopes and Mass Spectrometry:
● If 2 particles have the same charge:
○ lighter=deflected more
○ heavier=deflected less
○ Angle of deflection=mass to charge ratio
● Mass Spec:
○ Hard: breaks bond while ionizing, gives elemental analysis ration
○ Soft: ionize without breaking bonds, shows masses of each molecule
■ Which is more present in a mixture
● Isotopes: atoms of the same element with a different number of neutrons
○ Same atomic number (protons)
○ Different mass number (protons plus neutrons)
○ Percent Abundance: fraction of atoms of each isotope in a natural sample of an
element
■ %= number of atoms of a given isotope/total number of atoms of all
isotopes of element
Molecular Compounds Ionic Compounds
composition non-metal metal/non-metal
nanoscale Individual molecule Ions in crystal lattice
state Gas, liquid, solid, brittle/weak, Crystalline solid, hard/brittle
soft, waxy
Melting point low high
Boiling point low high
Heat transport low low
conductivity low Low (high if molten)
Module 3:
● Atoms often form stable ions by gaining or losing electrons until they match a noble gas
electron count
● Melting points: who has the most easily overcome force
○ High charge=strong force=highest melting point
○ High separation=lower melting point
Solutions:
● A solution is a uniform mix of 2+ pure substances
● Solvent is present in greatest abundance
● solute=any other solution component
● Electrolyte: substance that breaks down in solutions
○ strong=100% break into ions
