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Which of the following statements concerning wave mechanics is/are correct?   1. The energy of an electron is quantized.   2. The energy of an electron is equal to its mass multiplied by the square of its velocity.   3. Electrons travel in circular orbits around a nucleus.

What is the de Broglie wavelength of a 146-g baseball traveling at 99 mph?  (1 mi = 1.609 km and h =  6.63 × 10–34 J·s)

Which of the following statements is/are CORRECT?   1. FM radio waves have longer wavelengths than visible radiation and AM radio waves have shorter wavelengths than visible radiation.   2. Magnetic resonance imaging (MRI) uses a mixture of x-rays and gamma rays.   3. Exposure to ultraviolet (UV) radiation can lead to sunburns.

Which of the following colors of visible light has the longest wavelength?

A red laser pointer emits light at a wavelength of 488 nm. If the laser emits 7.5 × 10–4 J of energy per second in the form of visible radiation, how many photons per second are emitted from the laser?

For a proton (mass = 1.673 × 10–27 kg) moving with a velocity of 2.83 × 104 m/s, what is the de Broglie wavelength of the proton (in pm)?

Calculate the energy in the form of heat (in kJ) required to convert 325 grams of liquid water at 20.0 °C to steam at 115 °C. Assume that no energy in the form of heat is transferred to the environment. (Heat of fusion = 333 J/g; heat of vaporization = 2256 J/g; specific heat capacities: liquid water = 4.184 J/g⋅K, steam = 1.92 J/g⋅K)

What quantity, in moles, of hydrogen is consumed when 179.6 kJ of energy is evolved from the combustion of a mixture of H2(g) and O2(g)? H2(g) + O2(g)  →  H2O(l); ΔrH° = –285.8 kJ/mol-rxn

A 100 g sample of each of the following metals is heated from 35°C to 45°C. Which metal absorbs the lowest amount of heat energy? Metal Specific Heat Capacity copper 0.385 J/(g·°C) magnesium 1.02 J/(g·°C) mercury 0.138 J/(g·°C) silver 0.237 J/(g·°C) lead 0.129 J/(g·°C)

If 46.1 g of copper at 11.6 °C is placed in 85.0 g of water at 72.4 °C, what is the final temperature of the mixture? The specific heat capacities of copper and water are 0.385 J/g ⋅ K and 4.184 J/g ⋅ K, respectively.