CHEM 1110 Testbank page

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Chem 1110 - Quiz 5B - Fall, 2001

1. What is the wavelength in nanometers of light having a frequency of 4.5 x 1014 Hertz?

a) 1.50 x 10-3
b) 667
c) 6.6 x 10-7
d) 1.50 x 106
e) 440

2. What is the energy in Joules of a mole of photons of light having a frequency of 1.51 x 1014 typical of the visible region of the electromagnetic spectrum?

a) 1.0 x 10-19
b) 1.0 x 1019
c) 1.66 x 10-5
d) 6.02 x 1023
e) 6.04 x 104

3. The deBroglie wavelength of a typical electron in an atom is:

a) roughly the size of the nucleus of the atom.
b) many times larger than the size of the atom.
c) roughly the size of the atom itself.
d) so small that it doesn't matter.

4. Identify the INCORRECT statement below:

a) The maximum number of electrons that occupy the n=2 level in a many electron atom is 2.
b) The maximum number of electrons that occupy the 3s orbital in a many electron atom is 2.
c) The maximum number of electrons that occupy the 4d sublevel in a many electron atom is 10.
d) The maximum number of electrons that occupy the 4f sublevel level in a many electron atom is 14.

5. Excited Hydrogen atoms emit a photon of light in the visible region of the spectrum by falling to energy level n=2. This series of lines is called:

a) the Lyman series
b) the Bracket series
c) the Bohr series
d) the Balmer series
e) the Paschen series

6. A certain molecule emits a photon of light when making a transition from a quantum level having an energy of 1.20 x 10-18 J to a level of energy 4.04 x 10-19 J. What is the frequency of the emitted photon in s-1?

a) 250
b) 1.2 x 1015
c) 7.96 x 10-19
d) 2.5 x 10-7
e) 1.5 x 1014

7. Identify the INCORRECT statement below:

a) The number of unpaired electrons in the atom Cl is one.
b) The total number of electrons in the chloride ion is eight.
c) The number of valence electrons in the magnesium ion is zero.
d) The number of paired valence electrons in N is two.

8. Identify the INCORRECT statement below:

a) The l quantum number for the last electron added in the Aufbau procedure for forming the electron configuration of Sn is 1.
b) The ml quantum number for the last electron added in the Aufbau procedure for forming the electron configuration of Ca is 0.
c) The n quantum number for the last electron added in the Aufbau procedure for forming the electron configuration of Ga is 3.
d) The ms quantum number for the last electron added in the Aufbau procedure for forming the electron configuration of C could be either +1/2 or -1/2.

9. Consider the elements nitrogen and sodium. Which of the following is a CORRECT statement:

a) Nitrogen has the highest electronegativity and sodium has the highest ionization energy.
b) Sodium has the lowest ionization energy and nitrogen has the lowest electronegativity.
c) Nitrogen has the highest ionization energy and sodium has the largest radius.
d) Sodium has the lowest electronegativity and nitrogen has the largest radius.

10. Which of the following ion pairs are INCORRECTLY ranked according to size?

a) N3- < O2-
b) F- < O2-
c) Mg2+ < Na+
d) Na+ < F-
e) Al3+ < Na+

11. The most polar covalent bond would form between:

a) C and N
b) N and O
c) O and F
d) Cl and O
e) C and F

12. What is the total number of available valence electrons in the Lewis dot structure of the carbonate ion?

a) 26
b) 20
c) 2
d) 24
e) 22

13. What is the total number of shared pairs of electrons in the Lewis dot structure of I2?

a) 2
b) 1
c) 3
d) 0

14. What is the total number of unshared pairs of electrons in the Lewis dot structure of PBr3?

a) 0
b) 1
c) 9
d) 3
e) 10

15. Identify the INCORRECT electron configuration assignment below:

a) Na+ = 1s22s22p6
b) Al = 1s22s22p63s23p1
c) S = [Ne]2s22p4
d) Cr = [Ar]4s13d5
e) Rb = [Kr]5s1

16. Which species below does NOT possess at least one half-filled sublevel?

a) Cr
b) Mn
c) K
d) O
e) As

17. Identify the INCORRECT statement below:

a) Elements with high electronegativities generally have large atomic radii.
b) Electronegativity increases as you go from left to right across a period.
c) First ionization is the minimum amount of energy required to remove the most loosely held electron from a gaseous atom.
d) The second ionization energy of an element is always larger than the first ionization energy.
e) Atoms with low ionization energies tend to be larger than those with high ionization energies.

18. In which species below would one expect to find resonance structures?

a) CS2
b) O3
c) SF2
d) NCl3
e) CO

19. One expects to find at least one double bond in all but one of the following species. Which does NOT have a double bond?

a) CO2
b) O2
c) N2O
d) OF2
e) H2CO (C is the central atom)

20. In which species below is there NOT a violation of the octet rule?

a) CH3
b) BF3
c) PH3
d) BH3
e) SF6

21. Which of the following molecules contains polar covalent bonds and is a polar molecule?

a) CO2
b) N2
c) H2O
d) O2

22. What is the formal charge of the carbon atom in carbon dioxide?

a) 0
b) -1
c) -2
d) +1
e) +2

23. Construct the Lewis structure of lowest energy of an ionic species that contains one atom of N, S and C, and has an overall -1 charge. The Lewis structure will be as follows:








24. Which of the following was the reason for the failure of the Bohr atomic theory:

a) It assumed that the energy of the atom is quantized.
b) It assumed that the electron follows a well-defined orbital pathway.
c) It failed to account for the line emission spectrum of hydrogen.
d) It failed to predict the energy levels of the Hydrogen atom.

KEY

1)b 2)e 3)c 4)a 5)d 6)b 7)b 8)c 9)c 10)a 11)e 12)d 13)b 14)e 15)c 16)d 17)a 18)b 19)d 20)c 21)c 22)a 23)b 24)b