Gases

In this App Gases , we explore the relationships among pressure, temperature, volume, and the amount of gases. You will learn how to use these relationships to describe the physical behavior of a sample of both a pure gaseous substance and mixtures of gases. By the end of this chapter, your understanding of the gas laws and the model used to explain the behavior of gases will allow you to explain how straws and hot-air balloons work, why hand pumps cannot be used in wells beyond a certain depth, why helium-filled balloons deflate so rapidly, and how a gas can be liquefied for use in preserving biological tissue.

Learning Outcomes:

Calculate pressure and convert between pressure units with an emphasis on torr

and atmospheres.

Calculate P, V, n, or T using the ideal-gas equation.

Explain how the gas laws relate to the ideal-gas equation and apply the gas laws in

calculations.

Calculate the density or molecular weight of a gas.

Calculate the volume of gas consumed or formed in a chemical reaction.

Calculate the total pressure of a gas mixture given its partial pressures or given

information for calculating partial pressures.

Describe the kinetic-molecular theory of gases and how it explains the pressure

and temperature of a gas, the gas laws, and the rates of effusion and diffusion.

Explain why intermolecular attractions and molecular volumes cause real gases to

deviate from ideal behavior at high pressure or low temperature.

Describe the concept of pressure from a macroscopic and microscopic perspective.

Explain and apply Boyles, Charles', and Avogadro's gas Laws to observations of gas behavior.

Perform calculations using the ideal gas equation.

Define the conditions of STP and SATP.

Explain the relationship between the number density and mass density for a given gas including quantitative calculations relating mass, MW and density.

Describe the relationship between partial pressures and the total pressure as described in Dalton’s Law of Partial Pressure.

Perform calculations to determine the mole fractions of gases within and gas mixture and relate mole fraction to the partial pressure of a gas within a gas mixture.

Apply the concept of the gas laws to gas phase reactions and perform stoichiometric calculations using gas properties, masses, moles, limiting reagents and percent yield.

Explain the relationship between kinetic energy and temperature of a gas; between temperature and the velocity of a gas; and between molar mass and the velocity of a gas.

Describe the distribution of velocities for the particles in a gas sample and what factors affect this distribution.

Apply the ideas of kinetic molecular theory to a variety of gas phenomena such as diffusion and effusion.

Explain the quantitative relationship between T, V & n and P as described by kinetic molecular theory.

Describe macroscopic gas behavior using a small particle model of a gas.

State when the ideal gas model fails to predict the behavior of gases observed in nature and in the laboratory.

Explain what the breakdown of the ideal gas law tells us about the assumptions of kinetic molecular theory.

Explain the general principles of the hard sphere model and the vander Waal's model of gas.

Apply the concept of a scientific model to explain data not previously studied in class.

Finally remember it is expect students will be able to perform both composition and reaction stoichiometry problems .