1) When the elements are arranged in order of increasing number of protons, certain sets of properties recur periodically.

2) The early scientists who developed the quantum-mechanical model were bewildered by the model and it altered our fundamental view of matter.

3) Light is a type of matter.

4) Light travels through space at a speed of 3.00 × 108 m/s.

5) A red shirt appears red to our eyes because the shirt absorbs the red wavelengths of visible light.

6) A particle of light is called a packet.

7) A photon represents the mass of a single particle of light.

8) Blue light travels at a faster speed than red light.

9) A photon of red light contains the same amount of energy as a photon of blue light.

10) The shorter the wavelength of light, the more energy it has.

11) Wavelength of visible light determines color.

12) The most energetic photons are gamma rays.

13) Visible light makes up the largest portion of the electromagnetic spectrum.

14) Photons of ultraviolet radiation contain more energy than do photons of violet visible light.

15) X-rays damage biological molecules.

16) Ultraviolet light produces suntans and sunburns.

17) The heat you feel when you place your hand near a hot object is ultraviolet radiation.

18) In order for a substance to be heated in a microwave, it must contain water.

19) The great success of the Bohr model of the atom is that it predicted the emission spectrum lines of multi-electronic elements like helium.

20) Bohr showed that the emission spectrum of hydrogen was continuous with no interruption across the entire visible wavelength range.

21) Each element produces its own unique and distinctive emission spectrum.

22) An emission spectrum results when light emitted by glowing gas is passed through a prism.

23) When an atom absorbs energy, it often re-emits that energy as heat.

24) The energy of an electron orbit is quantized.

25) The energy of each Bohr orbit increases with increasing value of "n," but levels become more closely spaced as "n" increases.

26) Electrons behave like particles and we can describe their exact paths.

27) An orbital is a probability map showing exactly where an electron can be found in an atom.

28) The higher the principal quantum number, the lower the orbital energy.

29) The possible values for the principal quantum numbers are: .

30) The subshells of the orbital are represented by the possible letters: s, p, d, or f.

31) A principal shell with a value of n=3 would contain s, p, d, and f orbitals.

32) The subshells s, p, d, and f all have the same energy as long as they are in the same principal shell.

33) The ground state is when an electron in an atom is excited into the lowest possible vacant orbital.

34) The correct electron configuration for fluorine is: 1s22s22p5.

35) Transition metal elements always contain at least one "d" block electron.

36) The Pauli exclusion principle states that orbitals may hold no more than two electrons of identical spins.

37) The orbital diagram for fluorine shows 1 unpaired electron in a p orbital.

38) The correct electron configuration for magnesium is: 1s22s22p63s3.

39) The element manganese (symbol = Mn) has five valence electrons.

40) Bromine has 17 valence electrons.

41) Bromine has 28 core electrons.

42) The elements will lose or gain electrons as needed to have an electron configuration that matches a noble gas.

43) The ionization energy of lithium is higher than that of fluorine.

44) The atomic size of lithium is larger than the atomic size of nitrogen.

45) Based on relative location on the periodic table, a carbon atom is larger in atomic size than a phosphorous atom.

46) Based on relative location on the periodic table, vanadium (symbol = V) is expected to have more metallic character than selenium (symbol = Se).