Mnemonic Master: Remembering All Laws and Processes

Mnemonic 1: "I Am In Italy" (Four Processes — What is Zero)

Letter	Process	What is Zero
I	Isothermal	$\Delta U$ = 0 (internal energy unchanged)
A	Adiabatic	Q = 0 (no heat exchange)
I	Isochoric	W = 0 (no work done)
I	Isobaric	Nothing is zero (all three Q, W, $\Delta U$ are nonzero)

Alternative: "Isothermal: U stays, Adiabatic: Q quits, Isochoric: W waits, Isobaric: all play."

Mnemonic 2: Molecular Speed Order

"My Pet Antelope Runs Very Rapidly" Most Probable → Average → RMS = v_mp < v_avg < v_rms

Mnemonic 3: "Kelvin Only, Never Celsius" (Carnot)

For η = 1 − $T_{2}$ / $T_{1}$ , temperatures MUST be in Kelvin. Add 273 to every Celsius value before any calculation.

Mnemonic 4: "3-5-6 DOF" (Gas Types)

Monoatomic = 3 DOF (think: one atom = 3 directions to move)
Diatomic = 5 DOF (3 translation + 2 rotation, cannot rotate along bond axis)
Polyatomic = 6 DOF (3 translation + 3 rotation)

Mnemonic 5: γ Values — "5 over 3, 7 over 5, 4 over 3"

Monoatomic: γ = 5/3 (=1.67) → "Five thirds for the noble gases" Diatomic: γ = 7/5 (=1.4) → "Seven-five for $O_{2}$ , $N_{2}$ , $H_{2}$ " Polyatomic: γ = 4/3 (=1.33) → "Four thirds for the rest"

Mnemonic 6: Speed Formula "√2, √(8/π), √3 times RT/M"

v_mp = √(2RT/M); v_avg = √(8RT/πM); v_rms = √(3RT/M)

Coefficient sequence: √2 < √(8/π) < √3 ≈ 1.414 < 1.596 < 1.732 — ascending order.