For question #17, use the following picture:

17. what element is this? how do you know? (page 495 and periodic table pages 500-501)

for questions 18-21, use the information on pages 590-592 and page 567. in each space, classify the reaction type.
18. 2libr + pb(no3) pbbr2 + 2lino3
19. fe + 2hcl fecl2 + h2
¬¬¬20. cao + h2o ca(oh)2
21. nicl2 ni + cl2

The lights used by mark watley (played by matt damon) during the film the martian seem to be metal halide lamps. metal halide lamps are filled with vaporized mercury and metal-halogen compounds. when an electric current is passed through the lamp, the tube begins to glow a bright white/blue color. if you were to pass this light through a prism to separate the individual light frequencies, you would see a rainbow just as you would if using natural sunlight because of the complexity of the metal halide gas and the vast amount of possible electron transitions. (the study of light in this way is known as spectroscopy and allows astronomers to know exactly what atoms compose distant stars, simply by looking at the light they emit. the spectral lines an atom produces uniquely identifies that atom just like a fingerprint uniquely identifies a person. the momentum equation and energy equation that we have used above can be combined to give the following equation: c = e p where again p is the phonon momentum, e is the photon energy and c is the speed of light. when you divide the photon energy found in #6 by the photon momentum found in #4, do you get the speed of light? (if not, check your work for questions #4 through #6). yes no

Who was the first scientist to measure speed as distance over time?

A2.0 μf capacitor and a 4.0 μf capacitor are connected in series across a 0.827-kv potential. the charged capacitors are then disconnected from the source and connected to each other with terminals of like sign together. find the voltage across each capacitor.