CHM1310-001

Fall 2002

Exam #3 (100 pts.)

 

 

 

Name (Please print)________________________________

 

 

c = λυ;  E = hυ;  c = 3.0 x 108 m/s;  h = 6.63 x 10-34 J.s

 

1.(5)     The energy of electromagnetic radiation is

            (a) proportional to frequency

            (b) inversely proportional to frequency

            (c) independent of frequency

 

2.(5)     Which of the following wavelengths in the emission spectrum of hydrogen possesses the highest energy?

            (a) 656 nm, red

            (b) 486 nm, green

            (c) 434 nm, blue

            (d) 410 nm, violet

 

3.(4)     Is energy emitted or absorbed when the following electronic transition occurs:

            (a) n=6 à n=2

           

(b) n=6 à n=9

 

4.(5)     How many electrons can occupy a 5p subshell?

 

 

5.(4)     Given the following sets of quantum numbers, write the designation for the subshell to which the orbital belongs:

 

            (a) n=4, l=2

 

            (b) n=1, l=0

 

 

6.(6)     Write the complete electron configuration for Nb.

 

 

 

 

 

7.(8)     Draw the orbital diagram for the valence electrons of Rh.  How many unpaired electrons are there in Rh?

 

 

 

 

 

 

 

 

 

8.(4)     Identify the element with the following electron configuration:

 

[Kr] 5s24d105p1

 

 

9.(6)     Arrange these atoms in order of increasing atomic radius:  Mg, Al, Sr

 

 

 

10.(5)   Suppose the ionic radii of the carbon cation C4+ and the carbide ion C4- are compared to the atomic radius of the carbon atom.  With respect to size,

            (a)  C4+ > C4-

            (b)  C4+ < C

            (c)  C4- < C

            (d)  all are equal

 

11.(5)   Of the elements:  Al, N, P, and K, the correct order of increasing first ionization energy is, (from lowest to highest):

            (a)  K<Al<P<N

            (b)  K<P<N<Al

            (c)  N<Al<K<P

            (d)  N<P<Al<K

 

12.(8)   The difference between the 1st and 2nd ionization energy of Na is much greater than the difference between the 1st and 2nd ionization energy of Mg.  Explain.  (Hint – look at electronic configurations of the atoms and their ions.)

 

 

 

 

 

 

 

 

 

13.(8)   Describe the difference between an ionic bond and a covalent bond.

 

 

 

 

 

 

 

 

 

14.(5)   Of the elements As, N and O, the correct order of increasing electronegativity value is, (from smallest to largest)

            (a) O<As<N

            (b) N<O<As

            (c) As<N<O

            (d) N<As<O

 

 

15.(6)   Indicate whether each of the following bonds is polar or nonpolar.

            (a) O-F

            (b) C-F

            (c)  F-F

 

16.(8)   Draw the Lewis structure for SiH4.

 

 

 

 

 

 

 

 

 

17.(8)   Draw the Lewis structure for PO33-.