Practice exam

Which form of electromagnetic radiation has the longest wavelengths? A) gamma rays B) microwaves C) radio waves D) infrared radiation E) x-rays

C

Which of the following combinations of quantum numbers (n, l, ml, ms) do not represent permissible solutions of the Schrödinger equation for the electron in the hydrogen atom (i.e., which combination of quantum numbers is not allowed)? A) 9, 8, -4, 1/2 B) 8, 2, 2, 1/2 C) 6, -5, -1, 1/2 D) 6, 5, -5, 1/2 E) All are allowed.

C

Which of the following molecules has a nonlinear structure? A) XeF2 B) BeCl2 C) O3 D) CO2 E) N2O (central atom is N)

C

Which of the following does not contain at least one pi bond? A) H2CO B) CO2 C) C2H4 D) C2H6 E) All of the above (A-D) contain at least one pi bond

D

Draw the Lewis structures of the molecules below and use them to answer the following questions: I. BH3 II. NO2 III. SF6 IV. O3 V. PCl5 Which of these molecules show resonance? A) I, II B) II, IV C) II, V D) III, IV E) III, V

B

For the elements Cs, F, and P, the order of increasing electronegativity is: A) Cs < F < P B) Cs < P < F C) P < F < Cs D) F < Cs < P E) none of these

B

Germanium has __________ in its 4p orbitals. A) one electron B) two electrons C) three electrons D) four electrons E) none of these

B

How many of the following electron configurations for the species in their ground state are correct? I. Ca: 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 II. Mg: 1s 2 2s 2 2p 6 3s 1 III. V: [Ar]3s 2 3d 3 IV. As: [Ar]4s 2 3d 104p 3 V. P: 1s 2 2s 2 2p 6 3p 5 A) 1 B) 2 C) 3 D) 4 E) 5

B

How many of the following molecules possess dipole moments? BH3, CH4, PCl5, H2O, HF, H2 A) 1 B) 2 C) 3 D) 4 E) 5

B

If n = 2, how many orbitals are possible? A) 3 B) 4 C) 2 D) 8 E) 6

B

How many electrons can be described by the quantum numbers n = 3, l = 3, ml = 1? A) 0 B) 2 C) 6 D) 10 E) 14

A

How many f orbitals have the value n = 3? A) 0 B) 3 C) 5 D) 7 E) 1

A

Order the elements S, Cl, and F in terms of increasing ionization energy. A) S, Cl, F B) Cl, F, S C) F, S, Cl D) F, Cl, S E) S, F, Cl

A

Select the correct molecular structure for the given species from the choices below: 37. CO2 A) linear B) trigonal planar C) tetrahedral D) bent E) none of these

A

The molecular structure of SOCl2 is A) pyramidal B) none of these C) octahedral D) trigonal planar E) bent

A

What hybridization is predicted for the nitrogen atom in the NO3 - ion? A) sp2 B) sp3 C) dsp3 D) d 2 sp3 E) none of these

A

Which of the following atoms cannot exceed the octet rule in a molecule? A) N B) S C) P D) I E) All of the atoms (A-D) can exceed the octet rule

A

Which of the following atoms or ions has three unpaired electrons? A) N B) O C) Al D) S 2- E) Ti2+

A

Which of the following molecules contains a double bond? A) CO2 B) NH3 C) H2O D) all E) none

A

In Bohr's atomic theory, when an electron moves from one energy level to another energy level more distant from the nucleus: A) Energy is emitted. B) Energy is absorbed. C) No change in energy occurs. D) Light is emitted. E) None of these.

B

Metals typically have _______ electronegativity values. A) high B) low C) negative D) no E) two of these

B

Select the correct electron configuration for Cu. A) [Ar]4s2 3d9 B) [Ar]4s1 3d10 C) [Ar]4s2 4p6 3d3 D) [Ar]4s2 4d9 E) [Ar]3d10

B

The electron configuration for the barium atom is: A) 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 B) [Xe]6s 2 C) 1s 2 2s 2 2p 6 3s 2 3p 6 4s 1 D) 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 E) none of these

B

The molecular structure of XeF5 + is A) trigonal bipyramidal B) square pyramidal C) distorted tetrahedral D) octahedral E) none of these

B

Which of the following statements about quantum theory is incorrect? A) The energy and position of an electron cannot be determined simultaneously. B) Lower energy orbitals are filled with electrons before higher energy orbitals. C) When filling orbitals of equal energy, two electrons will occupy the same orbital before filling a new orbital. D) No two electrons can have the same four quantum numbers. E) All of these are correct.

C

Which of the following statements best describes the Heisenberg uncertainty principle? A) The exact position of an electron is always uncertain. B) The velocity of a particle can only be estimated. C) It is impossible to accurately know both the exact location and momentum of a particle. D) The location and momentum of a macroscopic object are not known with certainty. E) The location and momentum of a particle can be determined accurately, but not the identity of the particle

C

A (pi) bond is the result of the A) overlap of two s orbitals B) overlap of an s orbital and a p orbital C) overlap of two p orbitals along their axes D) sidewise overlap of two parallel p orbitals E) sidewise overlap of two s orbitals

D

According to the VSEPR model, the arrangement of electron pairs around NH3 and CH4 is A) different, because in each case there are a different number of atoms around the central atom B) different, because in each case there are a different number of electron pairs around the central atom C) the same, because both nitrogen and carbon are both in the second period D) the same, because in each case there are the same number of electron pairs around the central atom E) different or the same, depending on the conditions leading to maximum repulsion

D

Draw the Lewis structures of the molecules below and use them to answer the following questions: I. BH3 II. NO2 III. SF6 IV. O3 V. PCl5 Which of the molecules obeys the octet rule? A) I B) II C) III D) IV E) IV

D

In the Lewis structure for ICl2 - , how many lone pairs of electrons are around the central iodine atom? A) 0 B) 1 C) 2 D) 3 E) 4

D

In which case is the bond polarity incorrect? A) +H-F - B) +K-O- C) +Mg-H- D) +Cl-I - E) +Si-S -

D

Order the elements S, Cl, and F in terms of increasing atomic radii. A) S, Cl, F B) Cl, F, S C) F, S, Cl D) F, Cl, S E) S, F, Cl

D

The hybridization of the central atom in I3 - is: A) sp B) sp2 C) sp3 D) dsp3 E) d2sp3

D

Which of the following exhibits resonance? A) NH3 B) PCl5 C) H2O D) O3 E) At least two of the molecules (A-D) exhibit resonance

D

after what period can elements exceed the octet rule?

3

Atoms having equal or nearly equal electronegativities are expected to form A) no bonds B) polar covalent bonds C) nonpolar covalent bonds D) ionic bonds E) covalent bonds

C

Consider the skeletal structure shown below: N—C—C—N Draw the Lewis structure and answer the following: 45. How many pi bonds does the molecule contain? A) 0 B) 2 C) 4 D) 6 E) 7

C

Draw the Lewis structures of the molecules below and use them to answer the following questions: I. BH3 II. NO2 III. SF6 IV. O3 V. PCl5 How many of the molecules have no dipole moment? A) 1 B) 2 C) 3 D) 4 E) They are all polar.

C

In the cyanide ion (CN- ), the nitrogen has a formal charge of A) -2 B) -1 C) 0 D) 2 E) More information is needed

C

In the molecule XeF2, how many pairs of electrons surround Xe and what is the molecular geometry? A) 4, bent B) 4, pyramidal C) 5, linear D) 5, bent E) 6, linear

C

In the quantum theory, the magnetic orbital momentum quantum number is most directly associated with which property of orbitals? A) energy C) orientation B) size D) shape

C

Select the correct molecular structure for the given species from the choices below: 36. ClO2 A) pyramidal B) tetrahedral C) square planar D) octahedral E) none of these

E

The hybridization of the central atom in XeF5 + is: A) sp B) sp2 C) sp3 D) dsp3 E) d 2 sp3

E

Which of the following could not be a valid ml quantum number for a 4d orbital? A) 2 B) 0 C) -2 D) 1 E) 4

E

Which of the following statements is incorrect? A) Ionic bonding results from the transfer of electrons from one atom to another. B) Dipole moments result from the unequal distribution of electrons in a molecule. C) The electrons in a polar bond are found nearer to the more electronegative element. D) A molecule with very polar bonds can be nonpolar. E) Linear molecules cannot have a net dipole moment.

E

copper's electron configuration

[Ar] 4s1, 3d10

chromium's electron configuration

[Ar] 4s1, 3d5

carbon and hydrogen

always nonpolar

any 2 elements bonds (except carbon and hydrogen) are

always polar

element that always goes on the ouside of a lewis structure

hydrogen