BEHAVIOUR OF GASES.CHAPTER – 18.

THREE STATES OF MATTER.

1. SOLID.2. LIQUID.

3.GAS.

NO DEFINITE SHAPE / VOLUME.

MAIN FEATURES OF GASES.1.HIGHLY COMPRESSIBLE.

2. EXERT PRESSURE EQUALLY IN ALL DIRECTIONS.

3. MIX EVENLY IN ALL PROPORTIONS.

4. LEAST DENSE THAN OTHER STATES OF MATTER.

MAGIC BALLON.

FOR FIXED MASS OF GAS AT CONSTANT PRESSURE ,THE VOLUME EXPANDS OR

CONTRACTS AS THE TEMP.. VARIES.

CHARLES

GAY LUSSAC

“UNDER CONSTANT PRESSURE DEGREE RISE IN TEMP.., THE

VOLUME OF THE GAS INCREASED BY 1/273 OF THE

ORIGINAL VOLUME AT 0°C (273K)”

* “KELVIN” IS THE SI UNIT OF TEMPERATURE.

* TEMP.. – 273°C IS CALLED ABSOLUTE ZERO.(0K)

* AT 0K ALL GASES OCCUPU MINIMUM TEMP..

CHARLES LAW.“ AT CONSTANT PRESSURE, THE VOLUME OF A FIXED MASS OF GAS IS DIRECTLY

PROPORTIONAL TO ITS ABSOLUTE TEMP..”

V α T.V = KT.

(WHERE “K” IS PROPORTIONALITY CONSTANT.)

EQUATION FOR CHARLES LAW.

= K

APPLICATIONS OF

CHARLES LAW.

1. BALLOONS POPS OUT DURING HOT SUMMER THAN IN WINTER.

2. SODA BOTTLES STORED IN COOL & DRY PLACES.

ROBERT BOYLE.

RELATION B/W

VOLUME & PRESSURE OF GASES

WHEN TEMP.. IS

KEPT CONSTANT.

BOYLE’S LAW.“ AT CONSTANT TEMPERATURE,

THE VOLUME OF A GIVEN MASS OF DRY GAS IS

INVERSELY PROPORTIONAL TO ITS PRESSURE.”

DIFFUSION.• “ RANDOM MOVEMENT OF

GASEOUS MOLECULES FROM THE REGION OF HIGHER CONCENTRATION TO THE REGION OF LOWER CONCENTRATION.”

RATE OF DIFFUSION OF A GAS.

“ RATE OF DIFFUSION OF A GAS IS EQUAL TO THE VOLUME OF A GAS

DIFFUSING PER UNIT TIME”

“ THE RATE OF DIFFUSION OF A GAS

IS INVERSELY PROPORTIONAL TO

THE SQUARE ROOT OF ITS DENSITY”