Exam #3 Review Questions

Flashcards of Exam 3 review questions from provided lecture notes

Which scientist observed an increase in the λ of reflected photons when directing x-ray photons at graphite?

Compton

How many lone electrons does Gold (Au) have?

1

What total number of d-electrons does molybdenum have?

15

Using bond energies, how is the ΔH°rxn determined for the combustion of CH4?

-818 kJ

Which species has the smallest ionic radius among Xe, Te-2, I-, Ba+2, and Sb-3?

Ba+2

Which element in period 3 would most likely show a large increase in IE after IE5?

P

Which transition represents a Balmer (Visible) series transition?

n=5 → n=2

How many valence electrons does lead have?

4

Which transition releases the most energetic photon?

n=5 → n =1

Which of the following is an f-block element?

Tb

Which species is paramagnetic?

Ni+2

Rank Be, C, B, O, N, and Ne from least to greatest first ionization energy.

B<Be<C<O<N<Ne

How many lone pairs of electrons are on the central atom, P, in the preferred Lewis structure for PBr3?

1

Which Lewis structure for N2O BEST satisfies all of the rules for formal charges?

The structure with the lowest formal charges is preferred with the most negative formal charge placed on the most electronegative element (O)

How many resonance structures can be drawn for NO3 –?

3

Starting with which element do the s and d orbitals switch in sublevel energy?

Scandium

Which element has the greatest number of valence electrons among P, Te, In, Ba, K, and Al?

Te

Which rule is violated in the given electron configuration?

Hund’s Rule

What is the frequency (Hz) of a single photon of infrared light that emits 24.5 kJ/mol of energy?

6.14 × 1013

If the first ionization energy of indium is 558 kJ/mol, what is the wavelength (in nm) of a photon needed to ionize an indium atom?

214 nm

Ultraviolet light emits 2.5×10–17 J of light at a wavelength of 4.4×10–7 m. How many photons does this correspond to?

55

Which elements do not have an electron affinity?

Xe and Sr

Rank Ge, K, As, Se, Ca, and Br from least to greatest electron affinity.

Ca<K<As<Ge<Se<Br

What is the correct electron configuration for iodine?

1s22s22p63s23p64s23d104p65s24d105p5

What is the molecular geometry of the sulfur atom?

Bent

Which of the following bonds would have the largest dipole moment?

O-Si

Which is a typical hybridization for the oxygen atom?

Sp3

What is the molecular geometry of AsCl4 - ?

Seesaw

What is the hybridization of As for AsCl4 - ?

Sp3d

Which molecule is the most polar?

The cis-geometry due to having the largest dipole moment

Which elements are exceptions to the octet?

Se and Al

How many bonding pairs of electrons does the central atom have for BrO3 - ion?

Five

What is the hybridization of the central atom in XeF2?

sp3d

What is the bond order of the best Lewis structure of NO3 –?

1 1/3

What is the approximate angle of the O─C─O bond in the citric acid molecule?

120°

What is the electron and molecular geometries, respectively, of XeOF4?

octahedral, square pyramidal

Which of the following has the shortest bond?

C=O

Determine the wavelength (nm) of light absorbed when an electron in a hydrogen atom transitions from the n = 3 to the n = 5.

1283 nm

Which orbital is described by the quantum numbers n = 4, l = 2, ml = –1?

4d