Download Exam 1A Fall 2004

A. Mixon
Exam 1A: CH131 Fall 2004
Name:_________________________________ Date:___________________ Lecture:
9 a.m.
10 a.m.
Equations and Conversions
oF
1 kgm 2
1J =
sec 2
= 9/5oC + 32
oC
= 5/9[oF-32]
NA = 6.022 x 1023
1 cm3 = 1 ml
12 in = 1 foot
1 kg = 2.205 lb
5,280 ft = 1 mi
10 dm = 1 m
1 in = 2.54 cm
1 amu = 1.6606 x 10-24 g
SHOW ALL WORK!!! NO WORK, NO CREDIT!! SHOW ALL WORK!!! NO WORK, NO CREDIT!!
SHOW ALL WORK!!! NO WORK, NO CREDIT!! SHOW ALL WORK!!! NO WORK, NO CREDIT!!
SHOW ALL WORK!!! NO WORK, NO CREDIT!! SHOW ALL WORK!!! NO WORK, NO CREDIT!!
1.) Identify the following as physical or chemical changes (8 pts):
a. gallium melting
b. Sugar dissolving in coffee
c. Gasoline utilized by an automobile engine
d. Consumption of food
e. Milk spoiling
f.
logs burning
g. water boiling
h. oil floating on water
2.) Convert 198oC to oF and K (6 pts)
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A. Mixon
Exam 1A: CH131 Fall 2004
3.) You are given a box with the following dimensions: 2.00 ft by 4.00 ft by 3.00 ft. Would this
container be large enough to hold 575 lbs of iron. (the density of iron is 7.87 g/cm3)
4.) Convert 66
miles
meters
into
(6 pts)
2
hr
millisecon ds 2
5.) How many significant figures in 87,435.01 (1 pts)
6.) Element X has 25 protons and exists as an ion with 23 electrons. Identify the element and write
its symbol including the mass number, atomic number and charge:
7.) Calculate the molar mass of Ca(BO2)2 (4 pts)
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A. Mixon
Exam 1A: CH131 Fall 2004
8.) Calculate the number of protons, neutrons, and electrons in (12 pts):
Species
# of Protons
# of Neutrons
12C-4
52Cr+3
59Ni
16O
9.) Give the name of the element from the following symbols (12 pts):
a. B
b. H
c. Ca
d. Cl
e. K
f.
P
10.) Write molecular formulas for the following compounds (10 pts):
a. Calcium carbonate
b. Dinitrogen pentoxide
c. Carbon disulfide
d. Diboron heptanitride
e. Magnesium nitrite
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# of Electrons
A. Mixon
Exam 1A: CH131 Fall 2004
11.) Name the following compounds (14 pts):
a. Al(NO3)3
b. SO3
c. (NH4)2SO4
d. CCl4
e. NaOH
f.
N2O2
g. K3P
12.) Given the following isotopic data, calculate the average atomic mass for silicon. (10 pts)
Isotope
28Si
29Si
30Si
Mass (amu)
27.97693
28.976495
39.973770
13.) Calculate the mass, in grams, of 1.8066 x 1024 Sn atoms: (6 pts)
4
Abundance (%)
92.23
4.67
3.10
A. Mixon
14.)
Exam 1A: CH131 Fall 2004
How many Ba ions are there in 5.75 g of Ba3(PO3)2? (8 pts)
Bonus: (2pts) Explain the major contribution to the changing structure of the atom by either Thomson or
Rutherford. Draw a picture of their “theory” for the structure of the atom.
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