Download Page 1 of 4 Name PSCI 1055 Test #4 (Form B) Spring 2008 Buckley

Name ___________________
PSCI 1055
Test #4 (Form B)
Spring 2008
Buckley
Show your work on numerical problems to receive full credit for them.
1. (10 points) Balance each of the following chemical equations by writing the
appropriate coefficient on the underline. You may omit any coefficients that are
“1”.
___ Al
+
___ SO2 +
___ Fe3O4 Æ
___ Al2O3 + ___ Fe
___ O2 Æ ___ SO3
___ NaNO3 Æ
___ NaNO2 + ___ O2
___ Pb(NO3)2 Æ ___ PbO + ___ NO2 + ___ O2
___ H3PO4 + ____ KOH Æ
___ K3PO4 + ___ H2
___ C6H12O6 + ___ O2 Æ
___ CO2 +
___ Al
+
____ H2O
___ HCl Æ ___ H2 + ___ AlCl3
___ SrCl2 + ____ Na2SO4 Æ
____ SrSO4
+
___ NaCl
___ HBr + ___ Al2(CO3)3 Æ ___ H2CO3 + ___ AlBr3
___ Sr
+
___ H2O Æ ___ Sr(OH)2 + ___ H2
2. (4 points) A person working with a chemical solution found it has a pH of 5.4,
but wants it to have a pH of 7.2. Which of the following chemicals could be
added to raise the pH of the solution? Explain your reasoning.
NaOH
HNO3
H2SO4
HBr
Page 1 of 4
3. (8 points) Draw a structural formula meeting each of the following criteria.
a. an alkyl bromide containing at least five carbons and two chlorines
b. an amine containing at least five carbons and two amine groups
c. an alkene containing at least six carbons
d. an alcohol containing at least four carbons and two alcohol groups
4. (4 points) The mean distance from Jupiter to the Sun is 5.203 AU. Use Kepler’s
Third Law to find the period of revolution of Neptune. SHOW YOUR WORK.
Page 2 of 4
5. (8 points) Consider the H-R diagram below to answer the following questions.
a. Sirius is considered to be a class A star. What is the expected temperature
range of the Sirius?
b. What type of star has the lowest temperature but the highest level of
brightness on the H-R diagram?
c. A particular star has an absolute magnitude of 2.5. What type(s) of star
could this star be?
d. Suppose the star in part c is also found to have a temperature of 3500 K.
What type of star is this?
Page 3 of 4
6. (10 points) An old manuscript is found and carbon-14 dating is used to estimate
its age. Carbon-14 decays to N-14 with a half-life of 5730 years. A measurement
of the abundance of these two nuclides indicates there are now 4 parts of carbon14 to 12 parts of nitrogen-14.
a. How many parts of carbon-14 were in the original sample?
b. What fraction of the original carbon-14 remains now?
c. How many half-lives have transpired for the carbon-14?
d. Approximately how old is the sample?
Things that may be useful:
T2 = k R3
k = 1 yr2/AU3
Functional Groups:
Alcohol
-OH
Amine
-NH2
Carboxylic acid
O
||
-C - OH
Page 4 of 4