Name __________________________
Inorganic Chemistry
Exam 2
March 22, 2005
All work must appear on the exam!
(6 pts.) 1. Arrange the oxides Al2O3, B2O3,
BaO, CO2, Cl2O7, and SO3 in order
from the most acidic through amphoteric to the most basic.
most acidic: Cl2O7 > SO3 > CO2
> B2O3> Al2O3 (amphoteric) > BaO
(most basic)
(6 pts.) 2. Balance the following reaction in acid solution:
Fe+2 + MnO4- + ? à Fe+3 + Mn+2 + ?
oxidation half-reaction: Fe+2 ---> Fe+3 + 1e-
reduction half-reaction: MnO4- + 5e- + 8H+ ---> Mn+2 + 4H2O
common denominator of 5 e-
5(Fe+2 ---> Fe+3 + 1e-)
MnO4- + 5e- + 8H+ ---> Mn+2
+ 4H2O
--------------------------------------------------------
MnO4- + 5Fe+2 + 8H+ ---> 5Fe+3 + Mn+2
+ 4H2O
(4 pts.) 3. Calculate the number of fundamental vibrations for CO2.
(4 pts.) 4. Calculate the number of fundamental vibrations for H2O.
(6 pts.) 5. Describe the three raw materials and their purpose in the
operation of a blast furnace.
iron ore - source of iron
coke - reducing agent
limestone - slag former to help remove impurities
(3 pts.) 6. Explain why H3PO4 is a diprotic acid in water.
Water is not strong enough as a base to remove the third hydrogen ion from the acid.
(3 pts.) 7. Give the structural reason why H3PO3 is also a diprotic acid.
To be acidic, a hydrogen must be attached to an oxygen atom. In H3PO3, only 2 of the 3 hydrogen are so attached. The third hydrogen is attached directly to the P atom and is not acidic.
(4 pts.) 8. Use the distribution diagram to predict the ratio [H2PO4-]/[HPO4-2]
at pH 7.
[H2PO4-]/[HPO4-2] = 0.5/0.5 = 1
(2 pts.) 9. What is meant by the term pyrometallurgy?
This refers to metallurgy that cause the reduction of the metal ore with the aid of high temperature.
(6 pts.) 10. What is the standard potential Eo for the conversion
of HClO2 to Cl2.
Eo = (2(1.7) + 1(1.63))V/3 = 1.7V
(6 pts.) 11. Arrange the hydroxides Al(OH)3, Mg(OH)2, Si(OH)4, ClO3(OH), SO2(OH)2, and PO(OH)3 in order from the most acidic through amphoteric to the most basic.
most acidic ClO3(OH) > SO2(OH)2 > PO(OH)3 > Si(OH)4 > Al(OH)3 (amphoteric) > Mg(OH)2 (most basic)
(4 pts.) 12. The Lewis Acid AlCl3 is really a dimmer. Draw its structure.
Name _________________________
Inorganic Chemistry
Take Home Exam 2
Due: 12:00noon March 28, 2005
All work must appear on the exam!
13. Specify the following symmetry information for, Pt, N, and Cl atoms are coplanar
(3 pts.) (a.) Using your molecular models, determine the principal axis of rotation.
C2
(3 pts.) (b.) Determine if there are any non-coincident axes of rotation.
no
(3 pts.) (c.) Determine which type(s) of mirrors, if any are present.
sv
(3 pts.) (d.) Specify the point group for the molecule.
C2v
14. Specify the following symmetry information for Pt, N, and Cl atoms are coplanar
(3 pts.) (a.) Using your molecular models, determine the principal axis of rotation.
C2
(3 pts.) (b.) Determine if there are any non-coincident axes of rotation.
yes, C2 perpendicular to the C2 principal axis of reoation.
(3 pts.) (c.) Determine which type(s) of mirrors, if any are
present.
sh and sv
(3 pts.) (d.) Specify the point group for the molecule.
D2h
15. Specify the following symmetry information for
(3 pts.) (a.) Using your molecular models, determine the principal axis of rotation.
C3
(3 pts.) (b.) Determine if there are any non-coincident axes of rotation.
yes, C2 perpendicular to the C2 principal axis of reoation.
(3 pts.) (c.) Determine which type(s) of mirrors, if any are present.
sh and sv
(3 pts.) (d.) Specify the point group for the molecule.
D3h
(4 pts.) 16. With the aid of the Ellington diagram on page 180, above what temperature will carbon reduce FeO to Fe?
(2 pts.) 17. Give a metal that is produced by electrolysis.
aluminum, sodium, magnesium, copper
(2 pts.) 18. What are the products of the electrolysis of aqueous sodium
chloride?
sodium hydroxide solution and chlorine gas
(2 pts.) 19. What are the products of the electrolysis of molten sodium
chloride?
liquid sodium metal and chlorine gas
