Gaseous state

Force per unit area

How is pressure defined?

Pascal (Pa) = N/m²

What is the SI unit of pressure?

760 mmHg = 760 torr = 1 atm

What pressure values are equivalent to 1 atm?

101.325 kPa

What is 1 atm expressed in kilopascals?

100 kPa = 1 bar

According to IUPAC, what is the value of 1 bar?

Volume occupied by a gas

What is volume in gas laws?

1 L = 1000 mL

Convert 1 liter to milliliters.

1 mL = 1 cm³

Convert 1 milliliter to cubic centimeters.

Average kinetic energy of gas molecules

What does temperature measure in kinetic molecular theory?

Kelvin (K)

In what temperature scale must gas law calculations be performed?

K = °C + 273.15

How do you convert Celsius to Kelvin?

°F = (9/5 × °C) + 32

How do you convert Celsius to Fahrenheit?

°C = (5/9) × (°F − 32)

How do you convert Fahrenheit to Celsius?

STP

What does STP stand for?

1 atm, 273.15 K, 22.414 L/mol

What are the standard conditions at STP?

0.08205 L·atm/mol·K

What is the gas constant (R) commonly used in gas law problems?

8.314 J/mol·K

What is R in SI units?

1.987 cal/mol·K

What is R in calorie units?

Explains the behavior of gases and supports gas laws

What is the purpose of the kinetic molecular theory?

Atoms or molecules

What particles make up gases according to kinetic molecular theory?

Negligible molecular volume

What assumption does kinetic molecular theory make about the volume of gas particles?

No intermolecular attraction

What assumption does kinetic molecular theory make about forces between gas particles?

Continuous random motion

How do gas particles move according to kinetic molecular theory?

Perfectly elastic collisions

What type of collisions occur between gas molecules?

PV = k (constant T and n)

State Boyle's law equation.

Inverse relationship between pressure and volume

What relationship does Boyle's law describe?

Increasing pressure decreases volume

What happens to gas volume if pressure increases at constant temperature?

V/T = k (constant P and n)

State Charles' law equation.

Direct relationship between volume and temperature

What relationship does Charles' law describe?

Increasing temperature increases volume

What happens to gas volume when temperature increases at constant pressure?

P/T = k (constant V and n)

State Gay-Lussac's law equation.

Direct relationship between pressure and temperature

What relationship does Gay-Lussac's law describe?

Amonton's law

What is another name for Gay-Lussac's law?

V/n = k (constant P and T)

State Avogadro's law equation.

Direct relationship between volume and moles

What relationship does Avogadro's law describe?

Doubling the moles doubles the volume

According to Avogadro's law, what happens if the amount of gas doubles?

P₁V₁/T₁ = P₂V₂/T₂

State the combined gas law.

PV = nRT

State the ideal gas law.

Pressure, volume, temperature, or moles

What variables can be calculated using the ideal gas law?

Weight, molecular weight, and density

Besides P, V, T, and n, what else can be derived from the ideal gas law?

Real gas law

Which gas law accounts for intermolecular forces and finite molecular volume?

(P + an²/V²)(V − nb) = nRT

State the Van der Waals equation.

Internal pressure due to intermolecular forces

What does the Van der Waals constant a represent?

Excluded volume (gas particle volume)

What does the Van der Waals constant b represent?

Low pressure and high temperature

Under what conditions do gases behave most ideally?

High pressure and low temperature

Under what conditions do gases show non-ideal behavior?

Gas compression

When is non-ideal behavior most evident?

PV/RT = 1

What value does an ideal gas have for the compressibility factor?

Sum of the partial pressures of all gases

What does Dalton's law state?

Pₜ = P₁ + P₂ + … + Pₙ

State Dalton's law equation.

Pᵢ = XᵢPₜ

How is the partial pressure of a gas calculated using mole fraction?

Mole fraction

What quantity represents the fraction of total moles contributed by one component?

Xₐ + Xᵦ = 1

What is the sum of mole fractions in a binary mixture?

Escape tendency of molecules from a liquid

What is vapor pressure?

Partial vapor pressure equals pure vapor pressure × mole fraction

What does Raoult's law state?

Pₐ = P°ₐXₐ

State Raoult's law for component A.

Pₜ = Pₐ + Pᵦ

How is the total vapor pressure of an ideal binary solution calculated?

Ideal binary solution

In what type of solution does Raoult's law apply exactly?

Diffusion

What is diffusion?

Movement of gas molecules through another gas

How does diffusion occur?

Effusion

What is effusion?

Escape of gas molecules through a tiny opening

How does effusion occur?

Rate ∝ 1/√MW

State Graham's law using molecular weight.

Lighter gases diffuse faster

According to Graham's law, which gases diffuse more rapidly?

r₁/r₂ = √(MW₂/MW₁)

How do you compare the diffusion rates of two gases?

Carrier gas

Why is helium added to artificial air according to Graham's law?

C = kP

State Henry's law.

Gas solubility is directly proportional to pressure

What relationship does Henry's law describe?

Increasing pressure increases gas solubility

According to Henry's law, what happens when pressure increases?

Effervescence

What happens when pressure over a carbonated drink is suddenly released?

Decompression sickness (Caisson's disease)

What condition results from rapid ascent by scuba divers?

Nitrogen bubbles form in tissues and blood

What causes decompression sickness?

Hyperbaric oxygen therapy

What is the treatment for decompression sickness?

Relates vapor pressure to absolute temperature

What does the Clausius-Clapeyron equation describe?

Boiling occurs when vapor pressure equals external pressure

What is the definition of boiling point?

Vapor pressure increases

What happens to vapor pressure as temperature increases?

Water boils at a lower temperature

Why does water boil faster at higher altitudes?

Higher altitude lowers atmospheric pressure

Why is the boiling point lower at high elevations?

Ideal gas law

Which equation is commonly used to determine gas density and molecular weight?

Dalton's law

Which gas law is used to determine the partial pressure of oxygen collected over water?

Raoult's law

Which gas law is used to calculate vapor pressure lowering in ideal solutions?

Clausius-Clapeyron equation

Which equation is used to calculate vapor pressure at a different temperature?

Henry's law

Which gas law explains why unopened soft drinks retain dissolved CO₂?

Graham's law

Which gas law compares the diffusion rates of gases?

Boyle's law

Which gas law applies when only pressure and volume change?

Charles' law

Which gas law applies when only temperature and volume change?

Gay-Lussac's law

Which gas law applies when only temperature and pressure change?

Avogadro's law

Which gas law applies when only volume and number of moles change?

Combined gas law

Which gas law combines Boyle's, Charles', and Gay-Lussac's laws into one equation?