Chapter 5 Atomic Models Different metal containing compounds emit colored ligl when fireworks burn. This colored light is a combination of a series of colors called a spectral pattern (iE Each element emits its own characteristic spectral pattern, which can be used to identify the element This allowed the scientists in 1900s to develop models of the atoms internal structure
Chapter 5 Atomic Models Different metal containing compounds emit colored light when fireworks burn. This colored light is a combination of a series of colors called a spectral pattern. (谱带) Each element emits its own characteristic spectral pattern, which can be used to identify the element. This allowed the scientists in 1900s to develop models of the atom’s internal structure
5. 1 Models help us visualize the invisible world ofatoms Atom is very small in ing-Pong balls in the Earth
5.1 Models help us visualize the invisible world of atoms Atom is very small
We can not see them in the usual sense. This is because light travels in waves and atoms are smaller than the wavelengths of visible light, which is the light that allows the human eye to see things. So we can not see atoms through the media of light, even with a microscope An atom- A bacterum 106m (b) m
We can not see them in the usual sense. This is because light travels in waves and atoms are smaller than the wavelengths of visible light, which is the light that allows the human eye to see things. So we can not see atoms through the media of light, even with a microscope
We can see atoms indirectly through scanning tunneling microscope(STM), which was invented in 1980s. Figl: Scanning tunneling microscope fig3: an StM image of mono- Fig 2: an image of gallium laver of perylene derivative on and arsenic atoms graphite substrate, where the obtained with an stm epitaxial relationship is observed between the organic molecule and the substrate graphite
We can see atoms indirectly through scanning tunneling microscope (STM), which was invented in 1980s. fig3 : an STM image of monolayer of perylene derivative on graphite substrate, where the epitaxial relationship is observed between the organic molecule and the substrate graphite Fig1:Scanning tunneling microscope Fig2:an image of gallium and arsenic atoms obtained with an STM
5.2 Light is aform ofenergy requency(Hz) Gamma Ultra- Infrared Microwave Radio waves violet □留 X Sun lamps Heat Microway UHF TV FM radio VHE TV 400mm
5.2 Light is a form of energy