Question

In: Chemistry

1. How many vibrational modes do the following molecules or ions possess? [ Hints: Lewis structure...

1. How many vibrational modes do the following molecules or ions possess? [ Hints: Lewis structure may be helpful]

(a) NH3

(b) CO2

(C) C2H6

(d) NO2-

Solutions

Expert Solution

Answer:

a) NH3 : (C3V point group)

Ammonia is the Non linear molecule for this vibrational modes = 3N - 6

N = number of atoms

= 3 x 3-6

= 9-6

= 3

-N-H symmetric streching 3534 cm-1

-N-H Assymetric streching 3464 cm-1

-N-H Assymetric streching 3464 cm-1

-N-H Assymetric streching 3464 cm-1

b) CO2 :

It is the linear molecule

Vibrational modes = 3N - 5 N = number of atoms

= 3 x 3 - 5

= 4

-C-O Assymetric streching 2565 cm-1

-C-O symetric streching 1480 cm-1

c) C6H6: (D6h point group)

Planar molecule

Vibrational modes = 3N - 6 N =12

= 3 x 12 - 6

= 36 - 6

= 30

NO2- :

Non linear molecule

= 3N - 6 N = 3

= 3 x 3 - 6

= 9-6

= 3


Related Solutions

Draw a Lewis structure for each of the following molecules and ions. In each case the...
Draw a Lewis structure for each of the following molecules and ions. In each case the ions can only be corrected in one way. (a) Br2 (b) H2S (c) N2H4
Give the best Lewis structure for each of the following ions or molecules: In each case,...
Give the best Lewis structure for each of the following ions or molecules: In each case, state: The electron geometry around the central atom The VSEPR shape/molecular geometry around the central atom Whether or not the ion/molecule carries a permanent dipole. If a permanent dipole exists, use a crossed arrow to show its direction. A.) Iodine pentafluoride, IF5 B.) Selenium trifluoride ion, SeF3+
For each of the following molecules and ions: i.) Write the Lewis structure ii.) Indicate the...
For each of the following molecules and ions: i.) Write the Lewis structure ii.) Indicate the molecular geometry iii.) Indicate the approximate bond angles A.) Sulfur trioxide, SO3 B.) triiodide ion, I3- C.) sulfur hexafluoride, SF6
Draw the lewis structure for the following molecules ions NO2 , HOOH , HNO3 , N2O...
Draw the lewis structure for the following molecules ions NO2 , HOOH , HNO3 , N2O , H2SO4
Predict the symmetry species of the vibrational modes of the following molecules and indicate which are...
Predict the symmetry species of the vibrational modes of the following molecules and indicate which are IR and Raman active, please show your work. Identify the point group. a. NH3 b. ClF3 (T-shaped) c. PtCl2L2 (cis and trans) d. ML5 (square pyrimidyl) e. ML6 (octahedral)
Write the Lewis structure for the following molecules
Answer the following involving the Lewis structure: Write the Lewis structure for the following molecules Hydroxylamine (NH3O) Hydrazine N2H4   Draw the Lewis structures for all the important resonance form of NO-2. The following structures do not obey the octet rule. Draw a Lewis structure for each and state the type of octet-rule exception. 1. PF-62. XeF23. BH3   Draw the Lewis structure with lowest formal charges, and determine the charge on each atom in OCS.
Predict all bond angles and the shape of the molecules and ions. (draw Lewis structure first)...
Predict all bond angles and the shape of the molecules and ions. (draw Lewis structure first) BF4- HCO3- CH3CHO CH3COOH. 2.Indicate the polarity of the following molecules. Draw Lewis structure and point out the polarity of each chemical bond and then point our the polarity of the molecule. CH2Cl2 HCN H2O2 CH3CN
Two of these molecules / polyatomic ions cannot be adequately described using a single Lewis structure....
Two of these molecules / polyatomic ions cannot be adequately described using a single Lewis structure. Check the two formulas that must be written as a combination of resonance structures. Check all that apply: A) HCN B) OF2 C) NH4 D) O3 E) H2CO F) NO3^-
How many vibrational modes does an SO3 molecule have (a) in the plane of the nuclei,...
How many vibrational modes does an SO3 molecule have (a) in the plane of the nuclei, (b) perpendicular to the molecular plane?
Draw the Lewis structures for each of the following ions or molecules. For each, give (i)...
Draw the Lewis structures for each of the following ions or molecules. For each, give (i) the molecular shape, (ii) the electron pair geometry at the central atom, and (iii) the hybridization of the central atom. (a) H2Se (b) H2CO (C is the central atom) (c) BrF4 - (d) PF5 (e) SiF4
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT