GAS LAWS by yurtgc548

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```									      GAS LAWS-FOR CLOSED SYSTEMS
LAW OF                                            LAW OF GAY-
INCREASE AVERAGE
CHARLES                       KINETIC ENERGY(T)   LUSSAC

CAUSES
PV1    =      PV2                                 P 1V 1   =    P 2V 2
T1             T2                                 T1            T2
TEMP IS IN KELVIN                                 TEMP IS IN KELVIN
INCREASE OF
K = C + 273                     MOMENTUM          K = C + 273
CAUSES

INCREASED                                                  INCREASED
VOLUME IN AN                                               PRESSURE IN
EXPANDABLE                   INCREASE COLLISION                A RIGID
(CONSTANT
CAUSES                      CAUSES      (CONSTANT
FREQUENCY
PRESSURE)                                                    VOLUME)
CONTAINER                                                  CONTAINER
GAS LAWS
INCREASE EXTERNAL            LAW OF BOYLE
PRESSURE

P 1V 1   =    P 2V 2
CAUSES

T           T
TEMP IS IN KELVIN
INCREASE OF
EXTERNAL                 K = C + 273
COLLISIONS
CAUSES

DECREASED
VOLUME IN AN
EXPANDABLE       CAUSES       EXPANDABLE
CONTAINER PUSHED                CONTAINER AT
INTO SMALLER V                   CONSTANT
TEMPERATURE
•   THE LAWS OF GAY-LUSSAC (P and V) And the law of Charles (V and T) ARE
DIRECT PROPORTIONS – AS ONE INCREASES THE OTHER INCREASES
DIRECTLY.

BOYLES LAW IS AN INVERSE PROPORTION, AS P INCREASES, VOLUME
DECREASES. PV=k

•   P

V
PROBLEM SOLVING, GAS LAWS
• STEP ONE: ANALYZE. Read the problem an set up
• STEP TWO: CHECK UNITS, CONVERT NOW SO YOU
DO NOT FORGET       !
• STEP THREE: CRITICAL THINKING THE LOGIC! –
DECIDE WHAT IS CONSTANT AND WHAT IS
CHANGING, THEN DECIDE WHAT LAW TO APPLY.
• STEP FOUR: MAKE A LOGICAL ESTIMATION BASED
ON THE APPROPRIATE GAS LAW, THEN USE THE
EQUATION.
• STEP FIVE, CHECK, SUBSTITUTE IN YOUR ANSWER
TO SEE IF THE EQUATION CORRECTLY SOLVES FOR
A GIVEN.
EXAMPLE. CALCULATE THE VOLUME OF A 1.0L BALLOON THAT
IS PRESSURIZED FROM 1.0 ATM TO 2.0 ATM AT CONSTANT
TEMP.
•   STEP ONE: ANALYZE. Read the problem an set up your givens.
–   P#1 = 1.0ATM   LOGIC – PRESSURE AND VOLUME
–   P#2 = 2.0ATM   CHANGE,AT CONSTANT TEMP, THEREFORE
–   V#1 = 1.0L     THIS IS BOYLE’S LAW – WHICH IS AN
–   V#2 = X        INVERSE PROPORTION.

– AT CONSTANT TEMPERATURE

•   STEP TWO:CHECK UNITS – NET NEEDED HERE!
•   STEP THREE: CRITICAL THINKING THE LOGIC! – DECIDE WHAT IS
CONSTANT AND WHAT IS CHANGING, THEN DECIDE WHAT LAW TO
APPLY.
–   P#1 = 1.0ATM       PRESSURE IS INCREASING (DOUBLES),
–   P#2 = 2.0ATM       THEREFORE VOLUME WILL DECREASE

– V#1 = 1.0L
VOLUME WILL DECREAS (HALVED),
– V#2 = X
BECAUSE PRESSURE DOUBLED.
•   STEP FOUR: MAKE A LOGICAL ESTIMATION BASED ON THE
APPROPRIATE GAS LAW, THEN USE THE EQUATION.
– -BECAUSE PRESSURE DOUBLES, THE VOLUME WILL DECREASE
(IVERSELY PROPORTIONAL CHANGE). As the initial volume is 1.0 L the
final volume should be 0.50 L
•   P 1V 1   =   P 2V 2   à (1.0 atm)(1.0 L) = (2.0 atm)( X) à X= 0.50L
•    T1          T2

•   CHECK (FOR MATH ERRORS, THIS WILL NOT FIND LIGICAL ERRORS
AT ALL TIMES.)
– P1V1 = P2V2 à (1.0 ATM)(1.0L) = (2.0 ATM)(0.50L)

```
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