Practice questions#

1. What does light have to do with Chemistry?
Answer Light and electrons share similar properties
1. How did the idea of light and its particle and wave characteristics change?
Answer At first, it was thought electrons acted as particles and light was waves. This was later changed to say electrons and light can act as both a wave and a particle.
1. How is wavelength and frequency related? In your answer, define both.
Answer A wavelength's value is inversely proportional to frequency. This is because wavelength is the distance between points in a wave while frequency is the amount of waves per unit of time. This means if you have a short wavelength, lots of waves, the frequency would be high.
1. What is the equation to solve for wavelength or frequency?
1. Name each main category in the electromagnetic spectrum, highest energy first.
Answer Gamma rays, x-rays, ultraviolet rays, visible light, infrared rays, microwave, radio.
1. What is the range of wavelengths for the visible spectrum?
Answer ~400 nm - ~ 800 nm
1. What is the range of wavelengths for the whole electromagnetic spectrum (in meters)?
1. What did Max Plank and Albert Einstien discover?
Answer Using the photoelectric effect (think vending machine analogy), Plank thought up of, and Einstein discovered that light was not a wave but tiny packets of energy called photons.
1. What changes to the atom model was made to accommodate orbits? Also state which scientist discovered this
Answer Bohr created the Bohr model which included orbits, like rungs of a ladder, where the electrons stayed. Not randomly in a electron cloud like though before.
1. How does the Bright Line Spectrum relate to the new atom model?
Answer The bright lines seen in a bright line spectrum are actually electrons jumping down from their higher orbit. This is the electron going from its exited state to its ground state. The farther from the nucleus it is, means more energy it has, and the farther it jumps, the more total energy released which makes these different color of lights. Because different colors can only happen in certain locations that is why there are distant lines instead of a blend. It is unique to the atom because no two atoms have the same electron configuration.
1. What issues did Schrödinger’s model fix from the previous model?
Answer Bohr's model only really worked for Hydrogen and the specifics of how the electron 'jumps' did not seem possible so Schrödinger made some minor tweaks to make this more realistic. The new model had orbitals which were areas where electrons were extremely likely to be. But it was not impossible for an electron to be in the middle, for instance, as it was jumping down. This addition gave wave properties to the electron showing how and electron can both be a wave and a particle.
1. Describe the s, p, d, and f orbitals and what they are.
Answer Those are different orbitals where each letter represents the shape of the location where the electron could be. Each orbital can only have 2 electrons but p, d, and f, have multiple sets per larger orbital. The exact number is 1 for s, 3 for p, 5 for d, and 7 for f. Remember each of of those orientation will have at more 2 electrons in it.
1. What does an electron configuration of an atom look like and what does each part mean?
Answer An example of an electron configuration is 1s22s22p1. This is for the atom Carbon. The first number is the energy level (how far from the nucleus) and letter is what type of configuration it is, and the superscript number is the number of electrons in that sub level.
1. How can you use the periodic table to write an element’s electron configuration?