1. Pressure Cookers (Gay-Lussac's Law) Sealed container, constant V (approximately). Heating raises pressure → water boils above 100°C → food cooks faster. At 1.5 atm internal pressure, water boils at ~121°C.

2. Gas Cylinder Safety (Boyle's Law) Compressed gas in rigid cylinders at high P. If a cylinder is damaged and pressure is suddenly released (P drops), volume of gas expands dramatically (Boyle's Law). This is why gas cylinders must be stored away from heat and kept upright.

3. Submarine Ballast Tanks (Boyle's Law) Submarines control depth by adjusting air pressure in ballast tanks. Increasing pressure compresses air → water enters tanks → submarine descends. Releasing pressure → air expands → water exits → submarine ascends.

4. Isotope Separation — Uranium Enrichment (Graham's Law) ^{235}$UF_{6}$ (M = 349) and ^{238}$UF_{6}$ (M = 352) are separated by repeated effusion through porous barriers. Rate ratio = √(352/349) ≈ 1.004 (very close!). Requires thousands of stages for 90% enrichment. The slightly lighter ^{235}$UF_{6}$ preferentially effuses.

5. High-Altitude Cooking (Boiling Point) At 8,848 m (Everest summit): atmospheric P ≈ 0.33 atm. Water boils at ~71°C. Cooking pasta takes much longer at lower temperature. Solution: pressure cooker.

6. Supercritical $CO_{2}$ (Critical Constants) $CO_{2}$ above T_c = 31.1°C and P_c = 73.9 atm exists as a supercritical fluid — properties between liquid and gas. Used to: decaffeinate coffee, extract essential oils, dry cleaning (replaces organic solvents — more environmentally friendly).

7. Blood Nitrogen Bubbles — Decompression Sickness (Henry's Law tie-in) Scuba divers at depth breathe compressed air at high P. $N_{2}$ dissolves in blood (Henry's Law). Rapid ascent → P drops → $N_{2}$ comes out of solution as bubbles → "bends" (decompression sickness). Controlled ascent allows slow outgassing.

8. Spray Cans (Dalton's Law) Aerosol cans contain product gas + propellant (butane, propane). Total pressure = partial pressure of product + partial pressure of propellant. As product is used, mole fraction of propellant increases → same total P maintained as long as propellant is present.