27. Sodium has a work function of 3.65 x 10 19 J. Light that has a photon energy of 6.00 x 10 19 J is incident on a sodium surface. The maximum speed of the ejected electrons is A. 1.46 x 105 m/s B. 1.15 x 106 m/s C. 8.95 x 105 m/s D. 7.18 x 105 m/s28.A photon of gamma radiation strikes a free electron and is scattered. The scattered photon when compared to the incident photon, has a A. higher speed B. higher frequency C. longer wavelength D. greater momentum 29..When Maxwell's theory for the production of EMR is applied to a planetary model of atom, in which electrons orbit the nucleus in a manner similar to how moons orbit a planet the model is not supported because A. the nucleus must be positively charged B. accelerating charges must radiate energy C. almost all of the mass of the atom is contained in the nucleus D. line emission spectra can be explained using electron transitions

us sample of an unknown mixture of substances. When viewed tingset a cutfaction grating. the following spectrum is observer Spectrum of Unknown Mixture 500 nm 400 nm 600 nm 700 nm Spectra of Some Common Elements Mercury 500 nm 400 nm 600 nm Hydrogen 700 nm 500 nm 400 nm 600 nm Cadmium 700 nm 500 nm 400 nm 600 nm 700 nm Sodium 500 nm 400 nm 600 nm 700 nm Helium 500 nm 400 nm 600 nm 700 nm an Of the common elements listed above, the ones that could be in the mixture and A. hydrogen, sodium, and helium B. hydrogen, cadmium, and helium C. mercury, hydrogen, and helium mercury, cadmium, sodium, and helium D