Chemistry Comes Alive - Exam Review
Sheet
Matter & Energy
- Matter: Anything with mass & occupies space (solid, liquid, gas).
- Energy: Capacity to do work.
* Kinetic = in motion
* Potential = stored
* Forms: Chemical, Electrical, Mechanical, Radiant
- Energy conversions lose energy as heat.
Atoms & Elements
- Atom = smallest unit of element.
- Subatomic particles: Proton (+, 1 amu), Neutron (0, 1 amu), Electron (–, ~0 amu).
- Atomic # = protons; Mass # = protons + neutrons.
- Isotopes = same element, different neutrons.
- Radioisotopes: unstable, decay (medical use).
- Big 4 elements: C, H, O, N = 96% of body.
Molecules, Compounds, Mixtures
- Molecule = 2+ atoms bonded.
- Compound = 2+ different atoms bonded.
- Mixtures: physical combinations.
* Solution = homogeneous (salt water).
* Colloid = particles don’t settle (Jell-O).
* Suspension = particles settle (blood).
- Concentration: %, mg/dL, molarity.
Chemical Bonds
- Valence shell = outermost electrons.
- Octet rule: atoms want full outer shell.
- Ionic = electron transfer (NaCl).
- Covalent = sharing electrons (single, double, triple).
* Nonpolar = equal sharing.
* Polar = unequal sharing (H₂O).
- Hydrogen bonds = weak attractions, important in water, DNA, proteins.
Sheet
Matter & Energy
- Matter: Anything with mass & occupies space (solid, liquid, gas).
- Energy: Capacity to do work.
* Kinetic = in motion
* Potential = stored
* Forms: Chemical, Electrical, Mechanical, Radiant
- Energy conversions lose energy as heat.
Atoms & Elements
- Atom = smallest unit of element.
- Subatomic particles: Proton (+, 1 amu), Neutron (0, 1 amu), Electron (–, ~0 amu).
- Atomic # = protons; Mass # = protons + neutrons.
- Isotopes = same element, different neutrons.
- Radioisotopes: unstable, decay (medical use).
- Big 4 elements: C, H, O, N = 96% of body.
Molecules, Compounds, Mixtures
- Molecule = 2+ atoms bonded.
- Compound = 2+ different atoms bonded.
- Mixtures: physical combinations.
* Solution = homogeneous (salt water).
* Colloid = particles don’t settle (Jell-O).
* Suspension = particles settle (blood).
- Concentration: %, mg/dL, molarity.
Chemical Bonds
- Valence shell = outermost electrons.
- Octet rule: atoms want full outer shell.
- Ionic = electron transfer (NaCl).
- Covalent = sharing electrons (single, double, triple).
* Nonpolar = equal sharing.
* Polar = unequal sharing (H₂O).
- Hydrogen bonds = weak attractions, important in water, DNA, proteins.
