gas laws

Question 0

1. what is CHARLE’S law of gasses?
2. how is it stated mathematically?
3. what temp constant must be used?

Answer 0

1. CHARLE’S LAW: think “CP” pressure is the constant with charles law.
   - -at a constant pressure, the volume of a gas is directly proportional to the temp (temp=k).
   - -gasses expand when warmed and shrink when cooled
2. V1/T2=V2/T2; V=kT; V/T=k
3. must first convert temps to kelvin (k=kelvin temp)

Question 1

1. what is BOYLE’S law?

2. how do you calculate it?

Answer 1

1. BOYLE’S LAW: think “TB” temp constant with boyle’s
   at a constant temperature, volume is inverse to pressure:
   – as the pressure goes up, the volume goes down;
   –as the pressure goes down, the volume goes up.
2. P1V1=P2V2; V is proportional to 1/P; PV=k

Question 2

1. IDEAL GAS law aka?
2. what is the formula?
3. how do you interpret it?

Answer 2

1. combined gas law (combination of charle’s and boyle’s) ideal=combined.
2. PV=nRT (R is the constant or IDEAL gas; n= number of moles)
3. when n (number of moles) changes, the pressure or volume will change.

Question 3

DALTON’S law of partial pressures:

1. what is the formula?
2. how does it work?

Answer 3

1. P Total=P(A) + P(B) + P(C) etc.
2. in a gas mixture, each gas exerts its own partial pressure (oxygen=21% of 760 mmHg; nitrogen=78% of 760mmHg)
   .21 x 760=159 for O2; .78 x 760=592 for N2

Question 4

1. what is the standard for temperature for gas laws?

2. how do you convert to it?

Answer 4

1. kelvins
2. kelvin=celcius + 273
3. farenheit to celcius (9 degrees C= 5 degrees F-160), convert farenheit to celcius, then celcius to kelvin.

Question 5

1. what is GUY-LUSSAC’S law?
2. what is the equation?
3. what does it mean?

Answer 5

1. “vitamin G” volume is the constant in guy lussac’s (it is a modification of charle’s law).
2. P1/T1=P2/T2 (or P=kT or P/T=k)
3. at a constant volume, pressure of gas increases with temp (if you heat up a tank of gas, it could explode)

Question 6

example of Guy-Tussac’s law:

E cylinder with 1500 psi at room temp (70F) is heated to 350 degrees F by a fire. What is the new pressure?

Answer 6

1500 psi at room temp to 350 degrees F
1. 9(C)= 5(70) -160= ; 9(C)= 350-160=; 9(C)=190
9/9(C)=190/9=; C=21 (Kelvin=C+273);
21+273=294 degrees Kelvin; room temp=294 kelvin……NOW…

2. 9(C)=5(350)F-160; =9(C)=1750 -160= ; 9(C)=1590
   9/9 C= 1590/9=176 degrees celcius
   (kelvin=C + 273) 176 Celcius+273=449 degrees kelvin
   p1/t1=p2/t2»> 1500/294=x psi/449»>294x psi=673,500»
   673,500/294= 2,291 psi

Question 7

what does STP mean?

Answer 7

standard temperature and pressure (0 degrees celcius and 1 atm (or 273 degrees K and 760 mmhg))

Question 8

1. according to avagadro’s hypothesis, one mole of gas at STP occupies how many liters?
2. what does avagadro’s number state?

Answer 8

1. 22.4 L
2. one mole is the quantity of any substance containing the same number of particles as 12 grams. the number of particles is 6.02 x 10 to the 23rd power

Question 9

according to avagadro’s hypothesis; how many grams per 1 mole of each?

1. oxygen:
2. nitrous oxide:
3. how many liters of space does each one occupy?

Answer 9

1. 1 mole of oxygen=32 grams
2. 1 mole of nitrogen=44 grams
3. 22.4 L at STP (according to Avagadro’s law)