Gases

Question 1

force per unit area that the atoms or molecules exert on the walls of the container through collision
commonly expressed in units of atmospheres (1 atm) or millimeters of mercury (mmHg or torr)

Answer 1

Pressure (P)

SI Unit = Pascal (Pa) - 1 N / m^2, 1 atm = 760 mmHg = 760 torr

Question 2

expressed in liters (L) or milliliters (mL)

Answer 2

Volume (V)

SI Unit = Liters (L) or milliliters (mL)

Question 3

expressed as degrees Kelvin

Answer 3

T(K) = T(ºC) + 273 K

Question 4

standard conditions for a gas

Answer 4

298 K (25ºC)
1 atm

Question 5

standard temperature and pressure (STP)

Answer 5

273 K (0ºC)
1 atm

Question 6

4 Assumptions made by the kinetic molecular theory of gases (for an ideal gas)

Answer 6

1. Particles of a gas have no volume
2. No intermolcecular attractions between gas particles
3. Particles are in random motion, colliding elastically w/ one another and the walls of the cotainer
4. Avg KE of the gas particles is proportional to the absolute temp and is the same for all gases at a given temp

Question 7

For a given gaseous sample held at a constant temp (isothermal conditions), the volume of the gas is inversely proportional to its pressure

Answer 7

P1 * V1 = P2 * V2

*Boyle’s Law

Question 8

For a given gaseous sample held at a constant pressure (isobaric conditions), the volume of a gas is directly proportional to its absolute temp

Answer 8

V1 / T1 = V2 / T2

*Charles’s Law

Question 9

For a given gaseous sample held at a constant pressure and temp, the volume of a gas is directly proportional to the number of moles of gas present

Answer 9

n1 / V1 = n2 / V2

*Avogadro’s Law

Question 10

Equation: Ideal Gas Law

*Combines information from the other 3 gas laws

Answer 10

PV = nRT

Question 11

When we have a mixture of two or more gases in the same container, each exerts its own pressure known as _________

Answer 11

partial pressure

Question 12

Equation: Mole Fraction of a gas A in a mixture of gases

Answer 12

X(A) = number of moles of A / total number of moles of gases

Question 13

Equation: Partial pressure of a gas from its mole fraction

Answer 13

P(A) = P(t) * X(A)

Note: P(t) = total pressure of the system

Question 14

Equation: Total pressure from partial pressure

Answer 14

P(t) = P1 + P2 + P3…..

*Equal to the sum of the partial pressures of the individual components

Question 15

In a mixture of gases, each gas behaves ______ of the others, so the pressure that gas would exert would be the same as if it was in the container by itself

Answer 15

independently