E-CodeTI-84 Plus CE chemistry programs
11 checked chemistry programs for the TI-84 Plus CE. Each one runs in E-Code's virtual calculator in your browser, and you can put it on your own calculator.
The programs
- Weak acid equilibrium pH: Solves an ICE-table quadratic for [H+] and reports the pH.
- Ideal gas law solver: Solves PV=NRT for whichever variable is missing.
- Limiting reagent and theoretical yield: For aA + bB → cC from the grams and molar masses: moles of each reactant, which one is limiting, the theoretical yield in grams, the excess left over, and the percent yield if you give the actual yield.
- ICE table: equilibrium concentrations: General aA + bB ⇌ cC + dD with any starting concentrations and K: solves the ICE table for the shift x (forward or backward, by bisection on ln Q = ln K) and shows every equilibrium concentration with a Q/K check.
- Weak-acid titration and buffer pH: pH at any point of a weak acid + NaOH titration (start, buffer region, equivalence, excess base) with the equivalence volume, or the pH of an HA/A- buffer — both from the exact charge balance, with Henderson-Hasselbalch alongside.
- Rate laws: zero, first and second order: Integrated rate law for a zero-, first- or second-order reaction: concentration at time t, half-life, the time to fall to a target concentration, the rate at t, and which plot is linear.
- Nernst equation: cell potential and ΔG: From the two REDUCTION potentials (E°cell = E°cathode − E°anode), electrons transferred, temperature in kelvin and Q — E = E° − (RT/nF)·ln Q, which is 0.0592/n·log Q only at 25 °C: standard and actual cell potential, ΔG° and ΔG in kJ, log K, and whether the cell reaction is spontaneous.
- Combined gas law with °C or K: P1V1/(n1T1) = P2V2/(n2T2): type the two states as lists with U for the one unknown (a 0 also works where 0 is impossible; a Celsius temperature of 0 is 0 °C, so STP problems work); works in Celsius or Kelvin (Celsius is converted, the classic mistake) with any pressure and volume units used on both sides.
- Calorimetry: mixing and melting ice: Mix two substances (mass, specific heat, temperature) to the final temperature and heat exchanged, or drop ice below 0 °C into warm water: the final temperature, or how much ice melts when it can't all melt.
- Boiling point elevation, freezing point depression: Grams of solute, its molar mass, kilograms of solvent and the van 't Hoff factor: molality, the boiling-point rise and freezing-point drop, and the new boiling and freezing points (water, or your own Kb and Kf).
- Gas stoichiometry: grams to liters of gas: From grams of a reactant (its molar mass and coefficient) to the moles of a gas product (its coefficient) and that gas's volume at any temperature and pressure, plus the volume it would have at STP.