de Broglie Waves

What is the de Broglie wavelength of a 145 g baseball traveling at 30.0 m/s (67.1mph)? Is the wavelength much larger or smaller than the diameter of an atom(on the order of 100 pm)?

Bohr Theory: difference in energy between the two levels responsible for the violet emission line of the calcium atom

What is the difference in energy between the two levels responsible for the violet emission line of the calcium atom at 422.7 nm

electromagnetic waves

Light of wavelength 345 nm shines on a piece of calcium metal. What is the speed of the ejected electron?(Light energy greater than that of the work function of calcium ends up as kinetic energy of the ejected electron) work function for calcium= 4.34 x 10^-19 J

Bohr Theory

One of the lines in the Balmer series of the hydrogen atom emission spectrum is at 397nm. It results from a transition from an upper level energy level to n=2. What is the principal quantum number of the upper level?

Bohr theory: Calculate the wavelength of the transition from n=3 to n=2 for He+, a hydrogen-like ion.

A hydrogen-like ion has a nucleus of charge +Ze and a single electron outside this nucleus. The energy levels of these ions are -ZsquaredRH/n2 (where Z = atomic number). Calculate the wavelength of the transition from n=3 to n=2 for He+, a hydrogen-like ion. In what region of the spectrum does this emission occur?

Electron microscope: What energy must be imparted to each electron of the beam to obtain a wavelength of 10.0pm?

An electron microscope employs a beam of electrons to obtain an image of an object. What energy must be imparted to each electron of the beam to obtain a wavelength of 10.0pm? Obtain the energy in electron volts (eV) (1eV= 1.602x10^-19J )

pH/Ksp

what is the Ksp for Mg(OH)2 if a saturated solution in H2O has a pH of 10.53

percent disagreement and avogrado's number

How do you calculate the percent disagreement using a calculator for 1.01x10^19 (Avogrado's number of oleic acid molecules /mol? ( theoretical result being Avogrado's number) Please be specific because I am not quite sure how to do this on the calculator.

hydrate formula and Gravimetric of Cloride

1. Given that moles of water loss = Weight of water / GMW H2O (=18.051 ) and moles of CuSO4 = final weight/ GMW CuSO4 (=159.61) :Initial Weight: 116.877g (cooper II sulfate hydrate 30g + water ) :Final Weight: 19.177g (after heat compound with burner) :Weight of Water driven off (Initial weight - final weight) : 97. ...continues

Nuclear reactions: mass and time equations

A Cr3+ solution is electrolyzed using a current of 1.50 A. What mass of Cr is plated out after 24 hours, and what amperage is required to plate out 2.85 grams of Cr from a Cr3+ solution in a period of 2.50 hour?