Chemistry Fundamentals
What is the ideal gas law?
Redox equations are balanced by the half-reaction method: split into oxidation and reduction half-reactions, balance atoms and charge with electrons, then combine so electrons cancel.
Collision theory states reactions occur only when reactant particles collide with sufficient energy (≥ activation energy) and proper orientation.
Radioactive decay is the spontaneous emission of particles or energy from an unstable nucleus; common types are alpha (α, helium nucleus), beta (β, electron), and gamma (γ, high-energy radiation).
The ideal gas law is PV = nRT, where P is pressure (atm), V is volume (L), n is moles, R is the gas constant (0.0821 L·atm·mol⁻¹·K⁻¹), and T is absolute temperature (K).
Chemistry Fundamentals
What is a quantum number set?
The law of conservation of mass states that mass is neither created nor destroyed in a chemical reaction; total mass remains constant.
Avogadro's law states that equal volumes of gases at the same temperature and pressure contain equal numbers of molecules; volume is directly proportional to moles at constant T and P.
An electron configuration describes how electrons are distributed among the energy levels, sublevels, and orbitals of an atom, e.g., sodium is 1s² 2s² 2p⁶ 3s¹.
The four quantum numbers are n (principal, energy level), l mℓ (magnetic, orbital orientation), and ms (spin, +½ or −½), which together uniquely identify every electron.
Chemistry Fundamentals
What is a colligative property?
Electronegativity is the measure of an atom's ability to attract shared electrons in a chemical bond; it increases across a period and decreases down a group, with fluorine being the most electronegative element.
The boiling point is the temperature at which a liquid's vapor pressure equals atmospheric pressure, turning it into gas.
The four quantum numbers are n (principal, energy level), l mℓ (magnetic, orbital orientation), and ms (spin, +½ or −½), which together uniquely identify every electron.
Colligative properties depend on the number of dissolved particles, not their identity; examples are boiling-point elevation, freezing-point depression, and osmotic pressure.
Chemistry Fundamentals
What is the kinetic molecular theory?
A polymer is a large molecule made of repeating monomer units linked by covalent bonds, such as polyethylene (from ethylene) or proteins (from amino acids).
Le Chatelier's principle states that if a system at equilibrium is disturbed (by concentration, pressure, or temperature changes), the equilibrium shifts to counteract the disturbance.
The kinetic molecular theory explains gas behavior: particles are in constant motion, have negligible volume, elastic collisions, and kinetic energy proportional to temperature.
The oxidation number is the hypothetical charge an atom would have if all bonds were ionic; it is tracked to balance redox equations (e.g., H is +1, O is −2, free elements are 0).
Chemistry Fundamentals
What are the SI base units relevant to chemistry?
A polymer is a large molecule made of repeating monomer units linked by covalent bonds, such as polyethylene (from ethylene) or proteins (from amino acids).
The oxidation number is the hypothetical charge an atom would have if all bonds were ionic; it is tracked to balance redox equations (e.g., H is +1, O is −2, free elements are 0).
The five main types are synthesis (A + B → AB), decomposition (AB → A + B), single replacement (A + BC → AC + B), double replacement (AB + CD → AD + CB), and combustion (fuel + O₂ → CO₂ + H₂O).
Key SI units are the meter (length), kilogram (mass), second (time), mole (amount of substance), kelvin (temperature), ampere (current), and candela (luminous intensity).
Chemistry Fundamentals
What is osmotic pressure?
A reducing agent is the species that causes reduction by donating electrons and is itself oxidized; for example, H₂ in the reduction of metal oxides.
The four quantum numbers are n (principal, energy level), l mℓ (magnetic, orbital orientation), and ms (spin, +½ or −½), which together uniquely identify every electron.
Osmotic pressure is the pressure needed to stop the flow of solvent through a semipermeable membrane; it depends on solute concentration via π = iMRT.
Reaction rate is affected by concentration, temperature, surface area, catalysts, and nature of reactants.