Untitled Quiz

Density, Temperature, and Molarity

• Density formula: d = m/V (density equals mass divided by volume).
• Temperature conversion: C + 273 = K (Celsius to Kelvin).
• Molarity formula: M = moles/liter (molarity is moles of solute per liter of solution).

Chemical and Gas Laws

• Percent yield formula: (actual yield/theoretical yield) x 100 (measures efficiency of a reaction).
• Percent composition formula: (molar mass of element/molar mass of compound) x 100 (calculates proportion of an element in a compound).
• Boyle's Law: P1V1 = P2V2 (pressure-volume relationship in a gas).
• Charles' Law: V1/T1 = V2/T2 (volume-temperature relationship in a gas).
• Ideal Gas Equation: PV = nRT (relationship between pressure, volume, moles, gas constant, and temperature).
• Combined Gas Law: P1V1/T1 = P2V2/T2 (combination of Boyle's and Charles' laws).
• Gay-Lussac's Law: P1/T1 = P2/T2 (pressure-temperature relationship in a gas).

Heat and Enthalpy

• Heat capacity formula: C = ms (heat capacity equals mass times specific heat).
• Heat change with specific heat: q = msΔt (heat change equals mass times specific heat and temperature change).
• Heat change with heat capacity: q = CΔt (heat change equals heat capacity times temperature change).
• Standard enthalpy of reaction: ΔH°(rxn) = ΣnΔH°f(products) - ΣnΔH°f(reactants) (calculates enthalpy change from formation enthalpies).
• Enthalpy change from bond energy: ΔH° = ΣBE(reactants) - ΣBE(products) (calculates enthalpy change from bond energies).

Charge and Bonding

• Formal charges formula: (valence electrons) - (lone pairs) - 0.5(bonding electrons) = F.C. (determines charge on an atom in a molecule).
• Dipole moment: μ = Q x r (dipole moment equals charge times distance between charges).
• Bond order formula: 0.5(electrons in bonding orbitals - electrons in antibonding orbitals) (determines bond strength).

Chemical Kinetics

• Rate expression: rate = -Δ[A]/ΔT = +Δ[B]/ΔT (describes the change in concentration over time).
• Average rate: [ ]f - [ ]i / Tf - Ti (calculates the average rate of reaction).
• Rate law: k = [A]^x[B]^y (relationship between concentration and rate of reaction).
• First order rate law: rate = k[A] (first order dependence on reactant concentration).
• First order integrated rate law: ln[A] = -kT + ln[A]o (describes concentration change over time).

Reaction Order and Half-Life

• Overall reaction order: x + y (sum of the powers in the rate law).
• First order half-life: T1/2 = 0.693/k (time required for concentration to halve).
• Second order rate law: rate = k[A]^2 (rate is dependent on the square of concentration).
• Second order half-life: T1/2 = 1/k[A]o (specific to second order reactions).

Equilibrium and Acid-Base Chemistry

• Equilibrium concentration formula: Kc = products/reactants (calculates equilibrium constant for concentrations).
• Equilibrium pressure formula: Kp = products/reactants (calculates equilibrium constant for pressures).
• pH formula: pH = -log[H+] (calculates acidity).
• pOH formula: pOH = -log[OH-] (calculates basicity).
• Relationship: pH + pOH = 14.00 (sum of pH and pOH in aqueous solutions).
• Ion-product constant of water: Kw = [H+][OH-] = 1.0 x 10^-14 (product of hydrogen and hydroxide ion concentrations).

Acid-Base Relationships and Equations

• Percent ionization formula: (ionized acid concentration at equilibrium / initial acid concentration) x 100 (measures strength of acid).
• Relationship of Ka and Kb: (Ka)(Kb) = Kw (relationship between strengths of acids and bases).
• Henderson-Hasselbalch Equation: pH = pKa + log([conjugate base]/[acid]) (calculates pH based on weak acid/basics ratio).