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Chemistry Equations Table
| Boyle’s Law and Curve | At constant T—> PV=PV | |
| Charles’ Law and Curve | At constant P V/T=V/T | |
| Dalton’s Partial Pressure Law | Ptotal= ∑XiPtotal | Partial pressure= Mole fraction x P total P total= Sum of all the partial pressures |
| Faraday’s Law | I x time= n x F | F= 100000 (10⁴)Coulombs/mole e n= number moles of electrons Plates metal at the cathode (mass goes up) Corodes substance at the anode (mass goes down) |
| Graham’s Law for Diffusion/Effusion | Rate 1/ Rate 2= √M2/M1 | |
| Ideal Gas Law | PV= nRT | R= 8.314 P in Pascals V in m³ T in K |
| Van der Waal’s equation | Deviation from ideal gas behavior P (pressure)= [nRT/ V- nb] – [n²a/V²] | Essentially this is P= repulsion- attraction – b= bounce, the greater b is… more repulsion – a= attraction, the greater a is the less pressure there is |
Free Energy
| ΔG equation (Free energy equation) | ΔG= ΔH- TΔS ΔG=ΔG° + RTlnQ | ΔG – Free energy that is available to do work |
Moles
| Avogadro’s number for a mole | 6.02 x 10^23 molecules | |
| # moles | # moles = mass in grams/ molecular weight | |
| Molarity | Molarity = # moles of solute/ # of liters in solution |
Phases
| Phase Changes | ΔH fusion= – ΔH freezing ΔH vaporization= – ΔH condensation ΔH sublimation= – ΔH deposition | |
| Phase changes with MOST energy change | ΔH fusion +Δ H vaporization= ΔH sublimation | – Sublimation and Deposition= greatest enthalpy change – Vaporization and Condesnation= 2nd largest – Fusion and Freezing has LOWEST enthalpy change |
Pressure
| Osmotic pressure | π= MiRT | M= molarity R= 8.314 T in Kelvin |
Rate
| Rate Law | rate= k [X]ⁿ[Y]ⁿ | – Stoich coeffs are NEVER the exponents of a rxn UNLESS it is the ELEMENTARY rxn! – Always need to divide – Rate law of rxn is rate law of RDS |
| Arrhenius Equation | k= Ae ^ (-Ea/ RT) A is a constant | Low Ea means High T–> large K and FASTER rxn! e to a neg number means a decimal e to a larger number gives a larger number |
Solubility
| Ksp Calculations | Ksp for Ag₂SO₄= [Ag+]²[SO₄] Ksp= [2x]²[x]= 4x³ MAKE sure to square ALL NUMBERS! Ex: 3x³= 27x³ | Ksp= Solubility product constant Changes with TEMP/ Particle Size/ Polarity More positive the Ksp–> the more product will dissolve in solution at equilibrium |
| Henry’s Law | Solute concentration= kPsolute | Psolute= partial pressure of solute at solution’s surface Concentration of solute in solution is directly proportional to partial pressure of solute just above solution surface |
Temperature
| Boiling Point Elevation | ΔTb= Kb(i)m | m= molality |
| Freezing Point Depression | ΔTf=Kf(i)m | m= molality |
Thermodynamics
| First Law of Thermodynamics | ΔE= Q + W | Conservation of energy Change in total INTERNAL energy of system is equal to contributions from heat and work |
| Second Law of Thermodynamics | ΔS≥ q/ T | Isolated system will increase in entropy over time – Open system can decrease in entropy but at the expense of greater increase in entropy of surroundings In short- total entropy of universe is always increasing – REAL processes are never reversible–> entropy change is always greater than the heat transfer over temp |
