Chemistry 139
Practice Test 1
Name__________________
Show all work to receive full credit
1) (1.5 points) Give the symbol or name for the following elements.
a) selenium __________
b) potassium _________
c) Sc ___________
2) (1.5 points) To how many significant digits is each measurement expressed?
a) 500100 ft_______
b) 2.0304050 Gm________
c) 0.000678 kL ________
3) (3 points) Answer the questions a-c based on the ruler shown below.
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
grams
a) What is the measurement marked by the black line?
_______________
b) How many significant digits are in the measurement?
_______________
c) Did you correctly show the number of significant digits in part a. If not, how would you?
_______________
4) (5 pts) Determine the value of the following mathematical operation and express it in scientific notation with the proper
number of significant digits. Be sure to show work, don’t just show what’s on your calculator screen.
(3.9811x 102)-4 X (0.8000 x 10-1)2
(1.01 x 101) - 0.23512 + (11 x 10-2)
=
5) (5 points) The summit of Mount Everest is 29,035 ft above sea level.
a) Express this height in kilometers in scientific notation with the proper number of significant digits.
b) Convert your answer in part a to nanometers.
6) (10 points) How many grams of milk are in a 8.0 fluid ounce (fl. oz) glass? The density of milk is 64.4 lb/ft3. Express your
answer with the proper number of significant figures and in scientific notation.
Possible useful relationships:
1 quart = 2 pints (exact)
1 L = 33.82 fl. oz
1 pint = 16 fluid ounces (exact)
1 gallon = 3.785 L
1 pint = 2 cups (exact)
1 lb = 0.4536 kg
1 gallon = 4 quarts (exact)
7) (1 point) A standard iridium (Ir) block has a mass of 5.00010 grams. A student weighs this block on a variety of balances.
Which of the following measurements is the most accurate?
a) 5.1 grams
b) 4.999 grams c) 5.010000 grams
d) Cannot be determined without knowing the precision of each balance.
8) (0.5 points) If you are caught plagiarizing a homework assignment, what punishment will occur according to my syllabus
that is allowed by the student code of conduct.
9) (0.5 points) You need to contact me. Write my email, phone number, or office number.
10) (1 point) Consider the air that you are breathing right now. How would you categorize air according to the matter flow
chart?
11) (1 point) An raw egg is boiled for 10 minutes. Has a chemical or physical change occurred?