CHEMISTRY 1A

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Exam 1
CHEMISTRY 1A
100Points
Name______________________________
SHOW YOUR WORK FOR FULL CREDIT!!!!
Helpful hints: 453.59 g/pound, 1.0567 qt/liter, 1 kg = 2.20 lb, 16 ounces = 1 lb, 2.54 cm/in., 1 ounce = 28.4 g,
1 inch = 2.54 cm, 1 mile = 1.609 km. 1 cm3 = 1 mL
1. You have a 100.0 mL graduated-cylinder containing 50.0 mL of water. You drop a 154 g piece of brass,
dbrass = 8.56 g/cm3, into the water. How high does the water rise in the graduated cylinder?
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2. A rectangular piece of metal is 3.15 cm by 2.75 cm by 7.45 mm, and has a mass of 46.371 grams. The sample
is cut into small pieces and 29.86 grams of it placed in a graduated cylinder containing 37.5 mL of water.
Calculate the density of the metal and the new volume in the graduated cylinder.
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3. A room is 28 ft 6 in long, 17 ft 9 in wide, and 9 ft 3 in high.
Calculate the volume of the room in
a.
cubic feet.
b.
liters.
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4. Give the complete symbol for silver with 62 neutrons.
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5. How many electrons, protons, and neutrons are there in one atom of lead-214?
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6. A solid silver wire is 3.80 mm in diameter and 5.75 m long. V = r2l, dAg = 10.5 g/cm3. Silver sells for
$8.25/troy ounce, 23.90 g/troy ounce.
Calculate the
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a.
volume of the wire in cubic centimeters.
b.
mass of the wire in grams.
c.
the value of the wire.
7. The chlorine isotopes, 35Cl and 37Cl have masses of 34.96885 amu and 36.96590 amu respectively. The
atomic mass of chlorine is 35.453 amu. Calculate the percent abundance of these two isotopes if they are the
only naturally occurring isotopes of chlorine.
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8. Give the group number(s) for
a. the groups containing no metals.
b. group called alkali metals.
c. group called halogens.
d. the group containing exactly seven elements.
e. group called alkaline earth metals
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9. Consider an atom of 64Zn, calculate the density of the nucleus in grams per cubic centimeter, knowing that
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the nuclear radius is 4.8  10-6 nm and the mass of the 64Zn atom is 1.06  10-22 g. Vsphere = r 3
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