1300 CHEM Midterm Exam, Fall 2008
Part B: Short Answer
Page 1 of 1
Name: ____________________________
Student Number: ________________________
1. Balanced the chemical equation for the following neutralization reaction:
_____ Al(OH)3 (aq) + _____ H2SO3 (aq) _____ H2O(l) + _____ Al2(SO3)3 (aq)
2. How many protons, neutrons, and electrons are in the iron(III) ion, 56Fe3+?
_____ protons
_____ neutrons
_____ electrons
3. The element potassium consists of only three naturally occurring isotopes. What is the mass of
potassium-41, written to three significant figures? (See the table below.)
Isotope
Percent Abundance
potassium-39
93.2581 %
potassium-40
0.0117 %
potassium-41
?
Mass ___________ (amu)
38.963707
39.963999
?
Answer: amu
4. I am a third period element that does not like to be alone. In my natural state I like to pair up
with another atom of my type to form diatomic molecules in the gas phase. I react vigorously
with alkali metals to form ionic compounds. Write a balanced chemical equation for the
reaction between me in my diatomic form and an alkali metal residing in the fourth period.
Answer: _______________________________________________________________________
5. Write the ground state electron configuration
for Ni.
Answer: _________________________________
6. Draw a Lewis dot structure for: H2CO