CH-1010 Chapter Notes - Chapter 6: Sodium Chloride, Lattice Energy, Molar Mass
Document Summary
The macroscopic properties of substances, which we can readily observe and measure, arise from the microscopic interactions between the particles that make up those substances. Let"s see how this happens by looking at a group of elements that exist as single atoms: the noble gases. Note the correlation between them: boiling points increase as atomic numbers increase. To understand why this correlation exists, let"s think about what happens at the particle level when a liquid vaporizes. As we discussed in chapter 1, the particles in liquids (and solids) are in direct contact with each other. However, when a liquid vaporizes, the contacts are broken: the gas-phase particles that are attracted to each other takes energy, and the stronger the particles" attraction for each other, the greater the energy needed to separate them. German-american physicist fritz london proposed one explanation for these interactions in 1930.
