The Effect of Temperature on the Vapor Pressure of a Liquid
Learners examine how vapor pressure is calculated. The vapor pressure of a liquid increases with increasing temperature. If the heat of vaporization and the vapor pressure at one temperature are known, the vapor pressure at a second temperature can be calculated.
Vapor pressure is the pressure exerted by molecules in the gas phase in equilibrium with a liquid or a solid. Two examples are used to illustrate vapor pressure: the drying of clothes and the evaporation of ice.
In this animated object, learners examine how gas volume varies directly with absolute temperature (K at constant pressure). An example of a sample of gas at two conditions of volume and temperature is used to illustrate the law.
Learners observe that the volume of one mole of any gas is 22.4 L at standard temperature and pressure. An illustration shows that only the mass of the molar volume differs with the identity of the gas.
In this colorful, interactive object, learners examine how materials on the nanoscale compare with those on the macroscale. The focus is on the difference between macroscale and nanoscale gold in both color and melting point.
Boyle's Law states that gas volume varies inversely with the pressure at constant temperature and is described by the equation PV = constant. An example of a sample of gas at two conditions of P and V is used to illustrate the law.
In this brief object, learners examine the direct relationship between the volume of a gas sample and the number of moles of gas. A problem is presented so students can test their knowledge of Avogadro's Law.
Learners follow a four-step process to determine the empirical formula of a compound from the masses of its constituent elements. The molecular formula is determined in a fifth step using the molecular weight of the compound.