E-CodeCombined gas law with °C or K — a TI-84 Plus CE program
COMBGAS is a TI-BASIC program for the TI-84 Plus CE. 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.
What it asks for and what it shows
It asks for 2 values at its prompts, after you pick option 2 from its menu. In the example below it shows V2, RATIO.
Example run
One of its oracle test cases: “OpenStax Ex 9.10: 153 atm, 13.2 L, 27 C to 3.13 atm, 37 C”. The inputs are typed in order, and the results are the values the case expects on the screen.
| Step | Value |
|---|---|
| You enter | |
| Menu | option 2 |
| Input 1 | {153,13.2,1,27} |
| Input 2 | {3.13,0,1,37} |
| The screen shows | |
V2= | 666.7368552 |
RATIO= | 1 |
How it's checked
12 test cases, each checked against the textbook formula it uses. Replayed key by key on a virtual TI-84 Plus CE, they make 48 checks.
How E-Code checks every program
Run it or put it on your calculator
- Open the library in the TI-84 Plus CE calculator and pick “Combined gas law with °C or K” (COMBGAS).
- Put it on your own calculator with a computer and a USB cable, or type it in by hand.
Related programs
- Ideal gas law solver
- Weak acid equilibrium pH
- Limiting reagent and theoretical yield
- ICE table: equilibrium concentrations
- Weak-acid titration and buffer pH
All TI-84 Plus CE chemistry programs · All TI-84 Plus CE programs