Light and Matter
Which of the following exhibits wave properties, such as wavelength: electrons, protons, or cars?
All of the above!
What physical property or aspect of an orbital is described by the subshell quantum number label (l)?
The shape of the region of space occupied by the electron.
Which rule or principle states that electrons must occupy degenerate orbitals singly before pairing up?
Hund's Rule.
Rank the following neutral elements in order of increasing atomic radius: Si, Cl, Sn
Cl < Si < Sn
Provide the correct chemical formula for methane and dinitrogen monoxide.
CH4, N2O
What type of spectrum is represented by a dark background with four bright colored lines (at 410 nm, 434 nm, 486 nm, and 656 nm)?
An emission spectrum.
What is the maximum number of electrons that can occupy any single orbital, regardless of shell or subshell?
2 electrons.
Write the full electron configuration for a neutral Carbon atom and state how many unpaired electrons it possesses.
C: 1s^2 2s^2 2p^2
2 unpaired electrons in the 2p orbital.
When doing ES, do not forget to put element symbol with a colon!!!
Rank the following chemical bonds in order of increasing polarity: C-H, C-O, C-F, K-O.
C-H < C-O < C-F < K-O
Provide the correct chemical names for the following compounds: Na2S and SF6
Sodium Sulfide, Sulfur hexafluoride
Calculate the frequency (in Hz) of a UV light photon that has a wavelength of 200 nm (c = 3.00 x 10^8 m/s)
1.50 x 10^15 Hz (1/sec). Don't forget about Significant Figures, they will still be graded on for the rest of the class.
Calculate the total maximum number of electrons allowed in the n = 4 shell
32 electrons. 2n^2=2(4)^2=32! Or you could show the spdf math!
Write the noble gas core notation electron configuration for Phosphorus.
P: [Ne] 3s^2 3p^3
Rank the following species in an isoelectronic series in order of decreasing radius: Na^+, Mg^2+, F^-, Ne.
F- > Ne > Na+ > Mg2+
Name the following compounds containing transition metals or polyatomic ions correctly: Cr2(SO4)3 and HgNO3
Chromium(III) sulfate, Mercury(I) nitrate
Using an energy level diagram where E2 = -0.545 x 10^-18 J and E5 = -0.087 x 10^-18 J, calculate the energy of the photon absorbed when an electron undergoes a transition from n = 2 to n = 5.
4.58 x 10^-19 J
Provide a valid set of quantum number labels for the outermost (valence) electron in a neutral Potassium (K) atom.
Shell: 4
Sub-shell: S
Orbital: S
Spin: Up or Down (do not put +1/2 or -1/2 unless you are using the other labeling for quantum numbers (m, l, etc.)).
A photoelectron spectrum (PES) displays binding energy peaks at 28.6 MJ/mol (relative height 2), 1.72= MJ/mol (relative height 2), and 1.09 MJ/mol (relative height 2). Identify the element.
Carbon, 6 total electrons, neutral atom unless it says otherwise.
Rank the following elements in order of increasing first ionization energy: K, S, Cl, Ar.
Already in order.
K < S < Cl < Ar
Classify each of the following chemical bonds as purely covalent, polar covalent, or ionic: Li-Cl, C-H, Cl-Cl
Ionic, polar covalent, purely covalent
A UV sanitizer emits light at a wavelength of 250 nm Calculate the energy (in Joules) of a single photon emitted by this sanitizer (h = 6.626 x 10^-34 J x s, c = 3.00 x 10^8 m/s).
7.95 x 10^-19 J
Provide a suitable set of quantum number labels for one of the electrons in Silicon (Si) corresponding to its 2s^2 subshell peak.
Actually a simple question!
Shell: 2
Sub-shell: S
Orbital: S
Spin: Up or Down
A photoelectron spectrum displays binding energy peaks at 178 MJ/mol (relative height=2 ), 15.1 MJ/mol (relative height =2), 10.3 MJ/mol (relative height =6), 1.46 MJ/mol (relative height =2), and 0.79 MJ/mol (relative height =2). Identify the element and write its noble gas configuration.
Silicon
Si: [Ne] 3s^2 3p^2
Even though Calcium has a higher nuclear charge than Magnesium, explain why Calcium has a larger atomic radius than Magnesium.
Calcium's valence electrons occupy the 4th electron shell (n = 4), whereas Magnesium's outer electrons are in the 3rd shell (n = 3). Because the valence electrons in Calcium are in a higher principal quantum level, they are further away from the nucleus, resulting in a larger atomic radius despite the higher nuclear charge. If they were in the same shell, the answer would be different.
Write the chemical formulas for: Calcium hydroxide, Iron(III) sulfide, Dinitrogen pentoxide
Ca(OH)2, Fe2S3, N2O5