Ideal Gas Law (PV = nRT)

The gas-law member the lab chemistry set (mass-moles, molecular-weight, molarity) was missing.

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PV = nRT, solvable for any of pressure, volume, moles, or temperature, with R = 0.0820573 L*atm/(mol*K) and T in kelvin (entered in C). One mole of ideal gas fills 22.41 L at STP (0 C, 1 atm) and 24.47 L at 25 C, 1 atm. Solve for pressure (a heated/filled sealed vessel), volume (a gas-collection setup), or temperature (from a closed P-V state). Real gases deviate at high pressure or near condensation (van der Waals / Z factor separate); density needs the molar mass. A first-principles chemistry aid.

PV = nRT, R = 0.0820573 L*atm/(mol*K), T in kelvin (Tc + 273.15); solve n = PV/RT, P = nRT/V, V = nRT/P, or T = PV/(nR). Molar volume = V/n.

The ideal gas law (any general chemistry text; Brown/LeMay, Atkins). First principles.

The ideal gas law and the gas constant R are public first-principles chemistry; all four state variables are user inputs.

Verify protocol against your lab's SOP before pipetting. A miscalculated dilution can ruin a run or a sample.

Field names used by the API: solve_for, pressure_atm, moles, temperature_c, volume_l, molar_volume_l

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