Samples: Multiple-Choice Questions

1. Which of the following setups would be used to calculate the wavelength (cm) of a
   photon emitted by a hydrogen atom when the electron moves from the n= 5 state to the
   n= 2 state? (The Rydberg constant is RH= 2.18 × 10 –18J. Planck’s constant is

h= 6.63 × 10 –34J ⋅sec. The speed of light = 3.00 × 1010 cm/sec.)

A. 218 10..

5

1

2

(^181) 663 10
22
##---^34
id n i
B.
.
..
218 10
5
1
2
1
6 63 10 3 00 10
18
22
34 10

• 
  
  
  
  • 
    
  
  
  
  


• 
  

_ d

__

i n

ii

C.

.

..

663 10

5

1

2

1

2 18 10 3 00 10

34

22

18 10

#

##

• 
  
  
  
  • 
    
  
  
  
  


• 
  

_ d

__

i n

ii

D.

.

..

663 10

5

1

2

1

2 18 10 3 00 10

34

22

18 10

#

##

• 
  
  
  
  • 
    
  
  
  
  


• 
  

_ d

__

i n

ii

E.

.

..

663 10

5

1

2

1

2 18 10 3 00 10

34

22

18 10

#

##

• 
  
  
  
  • 
    
  
  
  
  


• 
  

_ d

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ii

Answer: B

The following relationships are needed to solve this problem:

ER

nn

∆ H^11 and hc∆E

if

=- =m :

eo 22

Combining these equations to solve for λgives the equation

.

.. sec

nn

cm

(^11) 218 10
5
1
2
1
6 63 10 3 00 10
R
hc
J
J sec
if
18
22
34 10 1
H
:

#:#:

• 
  

=

• 
  

m

• 
  

--

e 22 _ d

__

o i n

ii

2. A Co3+ion has ___ unpaired electron(s) and is ____.

A. 1, diamagnetic

B. 3, paramagnetic

C. 3, diamagnetic

D. 4, paramagnetic

E. 10, paramagnetic

Part II: Specific Topics