Chem Exam 3

Give the orbital designations of electrons with the following quantum numbers. n=2,l=1,ml=−1

2p

How many bonding electron pairs will N have in its molecules?

3

Give the orbital designations of electrons with the following quantum numbers. n=3,l=0,ml=0

3s

Give the orbital designations of electrons with the following quantum numbers. n=4,l=2,ml=0

4d

Give the orbital designations of electrons with the following quantum numbers. n=4,l=3,ml=−2

4f

In the ground-state electron configuration of Fe3+Fe3+, how many unpaired electrons are present?

5

How many unpaired electrons are there in a Cr atom?

6

What is the wavelength in meters of an X ray with frequency of 2.5 × 1018 Hz

1.2 × 10−10 m

Calculate the energy (in kJ) of 1 mole of yellow light photons with λ = 612 nm.

196 kJ

An orbital that as the appearance of a three-dimensional clover leaf has a quantum number l = ________

2

The Lewis electron-dot structure of N2 has ________ nonbonding electrons pairs, ________ bonding electron pairs, and a bond order of ________.

2,3,3

The Lewis electron-dot structure of H2CO has ________ nonbonding electron pairs, ________ bonding electron pairs, and a carbon-oxygen bond order of ________.

2,4,2

Which ionization process requires the most energy?

Al3+(g) → Al4+(g) + e-

In the molecule BrIBrI, which atom is the negative pole?

Br

The tripositive ion with the electron configuration [Ar]3d6 is ________.

Co3+

Place the following elements in order of decreasing atomic size: arsenic, sulfur, neon, cesium, calcium, and phosphorus. Rank from largest to smallest. To rank items as equivalent, overlap them

Cs, Ca, As, P, S, Ne

Which statement best describes an O3O3 molecule?

Each atom in ozone is connected to another atom by a bond having a bond order of 1.5.

What general trends in electronegativity occur in the periodic table?

Electronegativity increases from left to right across a period and decreases down a group.

What doubly positive ion has the following ground-state electron configuration? 1s22s22p63s23p63d6

Fe2+

Which of the following spheres is likely to represent a metal, and which a nonmetal?

Green sphere represents a nonmetal, blue sphere represents a metal.

Which sphere in the products represents a cation, and which an anion?

Green sphere represents an anion, blue sphere represents a cation.

Which of the following groups has the most favorable (most negative) electron affinity?

Group 7A

Which of the following covalent bonds has higher bond dissociation energy?

H-F

Which molecule contains the most easily broken carbon-carbon bond?

H3C−CH3H3C−CH3

Of the molecules HF and HCl, which has bonds that are more polar?

HF

Which of the following ions has the smallest radius?

Mg2+

Order the following compounds according to their expected lattice energies: LiClLiCl, KClKCl, KBrKBr, MgCl2MgCl2.

MgCl2,LiCl,KCl,KBrMgCl2,LiCl,KCl,KBr

Which step is usually the most energetically favorable in a Born-Haber cycle?

The formation of a solid ionic compound from gaseous ions

When two hydrogen atoms approach each other to form a chemical bond, different interactions occur between the atoms. Identify the correct statements with respect to the interactions involved in the formation of chemical bond.

When two atoms of HH approach each other, each electron is attracted by the other nucleus When two atoms of HH approach each other, the two nuclei repel each other.

Molybdenum has an anomalous electron configuration. Write the electron configuration of Mo using shorthand notation.

[Kr] 5s 14d 5

Of the following, which has the shortest de Broglie wavelength?

an airplane moving at a velocity of 400 mph

All four of the silicon-chlorine single bonds in SiCl4SiCl4 are polar. In which direction should the polarity arrows point?

away from the central silicon atom

According to the Balmer-Rydberg equation, transitions from nnn = 5 to mmm = 2 result in a photons of light that give rise to a spectral line with what color?

blue

Phosphorus pentchloride (PCl5PCl5) is used as a chlorinating reagent in chlorination of organic compounds. What type of bonding occurs between the atoms of a PCl5PCl5 molecule?

covalent

formula for formal charge

formal charge=valence e−−(nonbonding e−+bonding e−2)

The electronegativity is 2.1 for H and 3.0 for N. Based on these electronegativities, NH4 + would be expected to

have polar covalent bonds with a partial positive charges on the H atoms.

What type of bonding occurs in zinc(II) chloride, ZnCl2ZnCl2?

ionic

In general, at room temperature

ionic compounds are all solids, but covalent compounds may be solids, liquids, or gases.

Compared to ultraviolet radiation, infrared radiation occurs at ________ wavelengths, ________ frequencies, and ________ energies.

longer, lower, lower

What type of bonding occurs in a sample of pure barium, Ba? In other words, how is one barium atom held to another barium atom?

metallic

Which of the following is not a valid set of quantum numbers?

n = 3, l = 2, ml = 3, and ms = +1/2

Which of the following represent electron configurations that violate the Pauli exclusion principle? (A) [Ne]3s13p5 (B) [Kr]4d125s25p2 (C) [Ar]3d104s24p4

only (B)

Light behaves as if it were a stream of small particles, called ________, each having an amount of energy called a ________.

photons,quantum

The element in period 4 with the smallest first ionization energy is ________.

potassium

Which has the longer wavelength?

red light

Covalent bonding is

sharing of electrons

The ionic radius of Cs+ is ________ than the atomic radius of Cs, and the ionic radius of I- is ________ than the atomic radius of I.

smaller, larger

According to the Heisenberg uncertainty principle,

the position and momentum of a particle can be measured precisely, but not at the same time

NO2- is be expected to have

two identical bonds intermediate between a single and a double bond.

Which has the greater energy?

violet light

Which has the higher frequency, red light or violet light?

violet light