# Chapter 6 notes Flashcard

 What is wavelength (λ)?
 the distance between identical points on successive waves. (units = m or nm)
 What is amplitude?
 the vertical distance from the midline of a wave to the peak or trough. (E = 1/λ)
 What is frequency (v)?
 the number of waves that pass through a particular point in 1 second (Hz = 1 cycle/s = s-1)(s-1 = 1/s)
 What is the speed of a wave (u)?
 the product of the wavelength and frequency of the wave. (u = λv)
 What is the numeric value of the speed of light?
 C = 3.00 x108m/sor3.00 x1017nm/s
 In the electromagnetic spectrum what is the order of radiation types from highest to lowest energy order?
 Gamma rays, X rays, Ultra-violet, Infrared, Microwave, Radio waves
 Calculate the wavelength (in nm) of the red light emitted by a barcode scanner that has a frequency of 4.62 x1014 Hz. 1Hz = 1s-1
 C = λvλ = C/vλ = (3.00 x1017 nm/s / 4.62 x1014 s-1)λ = 649nm
 What is Planck’s quantum theory equation?
 E = hvE = energy of radiation (J)h = Plancks constant (6.63 x10-34 J.s.)v = frequency of radiation (s-1)
 What is Plancks constant?
 6.63 x10-34 J.s.
 What is the equation for the photoelectric efffect?
 E = hc/;
 The energy required to dislodge electrons from sodium metal via the photoelectric effect is 275kJ/mol. What wavelength in nm of light has sufficient energy per photon to dislodge an electron from the surface of sodium?
 The energy 275kJ/mol is for one mol of photons. To find the energy per photon, we must divide by avagadro’s numberE = (275kJ/1mol) x (1mol/6.022 x1023photon) x (1000J/1kJ)E = 4.567 x10-19 J/photonE = hc/λλ = hc/Eλ = [(6.63 x10-34- J.s.) x (3.00 x1017 nm/s)] /(4.567 x10-19 J)λ = 436nm
 When copper is bombarded with high-energy electrons, X rays are elimited. Calculate the energy (in joules) associated with the photons if the wavelength of the X rays is 0.154nm.
 E = hc/λE = [(6.63 x10-34 J.s.) x (3.00 x1017 nm/s)] / (.154nm)E = 1.29 x10-15 J
 What is Bohr’s equation?
 E(n) = -RH(1/n2)
 The change in energy when an electron undergoes a transition from one energy level to another is given by what equation?
 ;E = -RH [(1/nf2) – (1/ni2)](RH = 2.18 x10-18 J)
 Calculate the wavelength (in nm) of a photon emitted by a hydrogen atom when its electron drops from then = 5 state to the n = 3 state.
 ;E = -RH [(1/nf2) – (1/ni2)];E = -2.18 x10-18 J [(1/32) – (1/52)];E = -1.55 x10-19 JE = hc/;; = hc/E; = [(6.63 x10-34 J.s.) x (3.00 x1017 nm/s)] /(1.55 x10-19 J); = 1280nm
 What is the de Broglie equation?
 ; = h/mv
 Calculate the wavelength of an electron traveling with a speed of 2.65 x106 m/s.;(mass of electron = 9.10939 x10-28 g)(1J = 1kg m2/s2)(h = 6.63 x10-34 J.s.)
 ; = (6.63 x10-34 kg m2/s2 s) / [(9.10939 x10-31 kg) x (2.65 x106 m/s)]; = 2.74 x10-10 m
 Calculate the wavelength (in nm) of a H atom (mass = 1.674 x10-27 kg) moving at a speed of 7.00m/s;(1J = 1kg m2/s2)
 ; = h/mv; = (6.63 x10-34 kg m2/s2 s) / [(1.674 x10-27 kg) x (7.00 m/s)]; = (5.66 x10-8 m) x (1 x109 nm/1m); = 56.6nm
 What is the Heinsberg Uncertainty Principle?
 it is impossible to know simultaneously both the position and momentum of a particle as small as an electron
 If l = 0, what orbital is it in?
 s orbital
 If l = 1, then what orbital is it in?
 p orbital
 If l = 2, what orbital is it in?
 d orbital
 if l = 3, what orbital is it in?
 f orbital
 Which set of quantum numbers is permissible for; an electron in an atom?;a) n =1, l = 1, ml = 0, ms = +1/2b) n = 3, l = 1, ml = 2, ms = -1/2c) n = 2, l = 1, ml = 0, ms = +1/2d) n = 2, l = 0, ml = 0, ms = +1
 a) n =1, l = 1, ml = 0, ms = +1/2b) n = 3, l = 1, ml = 2, ms = -1/2c) n = 2, l = 1, ml = 0, ms = +1/2d) n = 2, l = 0, ml = 0, ms = +1
 What does paramagnetic mean?
 elements and compounds that have unpaired electrons and are attached to a magnet
 What does diamagnetic mean?
 substances in which all electrons are paired and are slightly repelled by a magnet
 What is the Pauli exclusion principle?
 no two electrons in an atom can have the same four quantum numbers.