chemistry chapter 14: gas laws

sublimation

phase transformation from solid phase directly to vapor phase

vapor pressure

the force created by a liquid when it evaporates

boiling point

the temperature at which a liquid's vapor pressure equals atmospheric pressure, causing it to change into a gas

evaporative cooling

the process by which a liquid absorbs energy and cools as it evaporates, resulting in a temperature drop

allotropes

different molecular forms of the same element in the same physical state

kinetic molecular theory

uses the motions of particles (atoms and molecules) to explain temperature, pressure, and states of matter.

assumptions the kinetic theory makes about gas

-Its particles have insignificantly small volume

-There are no intermolecular forces

-Their collisions are perfectly elastic - energy is not lost in collisions

-They are moving at very high speeds and in random directions

-The particles are hard and spherical

the collisions of gas particles with the walls of their container

According to the kinetic theory, what causes gas pressure?

vacuum

A space devoid of matter, including air

atmospheric pressure

the result of the random movements of air particles; thus it acts in all directions.

barometer

measures atmospheric pressure by balancing the weight of a column of mercury against the pressure exerted by the surrounding air. It consists of a glass tube filled with mercury, inverted into a basin of mercury, and the height of the mercury column indicates the atmospheric pressure.

Why water boils in a vacuum

Water boils in a vacuum because the decreased atmospheric pressure reduces the boiling point, allowing it to vaporize at lower temperatures

Why vaporization causes the temperature of a liquid to drop

because the molecules that escape into the vapor phase carry energy away from the remaining liquid, resulting in a decrease in temperature.

the relationship between an object’s temperature and the average kinetic energy of its particles

an increase in temperature corresponds to an increase in the average kinetic energy of the particles within a substance. As temperature rises, particles move more rapidly, leading to higher energy states.

Why gases are easily compressed

because their particles are far apart, allowing for significant reduction in volume when pressure is applied.

the unit temperature must always be in when using the gas laws?

kelvin

ideal gas

a hypothetical gas that perfectly follows the gas laws under all conditions, with assumptions including negligible particle volume and no intermolecular forces

boyles law

the relationship between volume and pressure of a gas, if temperature and amount are held constant

charles law

the relationship between temperature and volume of a gas, if the pressure and amount are kept constant

gay lussacs law

the relationship between pressure and temperature of a gas, if the amount and volume are kept constant

combined gas law

the amount of gas is kept constant, the relationship between volume, temperature, and pressure

avogrados law

the relationship between the amount of a gas and the volume, if temperature and pressure are kept constant

ideal gas law

describes the behavior of an ideal gas based on the relationship between pressure, volume, temperature, and the number of moles of gas

ideal gas constant

a proportionality constant in the ideal gas law equation, typically denoted as R=8.31

the conditions the behavior of a real gas most differ from the ideal gas model

occur at high pressure and low temperature where intermolecular forces become significant and gas particles are closer together

types of gasses most likely to deviate from the ideal gas model

polar gases and those with high molar mass, as they experience stronger intermolecular forces that affect their behavior.

partial pressure

The pressure exerted by a gas in a mixture

Dalton’s Law

the pressure of the mixture is just equal to the pressures of the individual gases added together