Name ________________________________ Period ______ Date Due _____________________
____/10 Points
Unit 1 Study Guide
Learning Targets & Sample Questions (sample problems in italics)
Measurement, Units, Problem Solving and Calculations: Review Chapter 1, Chemistry: An
introduction and review Chapter 2, Measurements and Calculations. Be sure to review your notes,
assignments and labs as you prepare for the upcoming test.
1. Apply significant figures rules in all calculations.
- how many significant figures are in these measurement numbers:
-3
5
0.0910, 1.75 x 10 , 692, 10.3, 56,000, 6.780 x 10
-Round: 0.34373 to 3 significant figures;
23,456 to 3 significant figures;
5,449 to 2 significant figures.
− Consider the addition of 250 to 15.4. What is the mathematical answer? If these were
length measurements (250 mm + 15.4 mm) what answer would you report, and why?
− Consider multiplying 6.2 x 16.43. What s the mathematical answer? If these were
measurements, (6.2 mL x 16.43 g/mL) what answer would you report, and why?
− Write 231,000 in scientific notation, indicating 3 significant figures.
− How could you indicate a measurement of 100 was significant to 2 significant figures?
2. Know how to do calculations using scientific notation. YOU NEED YOUR OWN
CALCULATOR for the test.
3. Use scientific notation in calculations whenever convenient.
14
–12
(3.1 x 10 ) (4.4 x 10 )
–14
-2
–6.6 x 10 (2 x 10 )
1/ 0.00032
5
-4
(5 x10 )(10 )
-2
(2 x10 )
4. Know the SI units for length, mass, temperature, and time. What is the SI unit for length? Mass?
Volume? Temperature?
5. Know the metric units of common quantities used in chemistry, and their relative sizes: grams = mass;
liters = volume; meters = length; seconds = time; also, that 1cm3 = 1mL
What metric unit would be most appropriate to describe a gallon of gasoline?
Measuring the thickness of a human hair?
Describe a pound of hamburger?
Name ________________________________ Period ______ Date Due _____________________
6. Be able to convert within the metric system using units for length, mass, volume and combinations of
units.
Understand the metric system units and multipliers (prefixes) for measuring length,
volume, and mass.; e.g., for grams: 1kg = 1000 g; 1 g = 10 dg; 1 g = 100 cg; 1 g =
1000 mg. Know the meaning (multiples of powers of ten) of the metric prefixes: kilo = 1000 or
103; deci- = 1/10 = 0.1 = 10-1; centi- = 1/100=0.01 =10-2; milli- = 1/1000= 0.001 = 10-3
- Using different unit (prefixes), how many ways can you write 0.5 L?
− How many meters in 120 cm? in 3.65 km?
− Which is larger, 150 mm or 1.3 cm?
− What is the prefix to indicate 1/1000 of a unit? To indicate 1000 of a unit?
7. Be able to use units and unit analysis (dimensional analysis) to solve problems
A. Write conversion factors using equivalent quantities and units.
B. Set up multiplication steps to cancel (like factors) units – showing units!
Convert 10.3 cm to ft. (1 in = 2.54 cm, 12 in = 1ft )
Convert 9.83 kg to pounds. (1 pound = 453.6 g)
Convert 1.83 m to inches. (1 cm = 2.54 in )
8. Be able to calculate density or use density to find mass or volume. D= m/vol; typical units = g/mL or
g/cm3
Calculate the density in g/mL or g/cm3 given mass = 234 g and volume = 2.2 cm3.
Calculatethe density in g/mL or g/cm3 given mass = 1.2 lbs and volume = 2.2 ft3. (1 lb =
453.59 g; 1in = 2.54cm)
Calculate the mass in g if the density of an object is 0.88 g/ml and you have 50 mL.
Lab Practice:
1. Be able to name different pieces of lab equipment. Match with names (see the drawing handout for
others):
Name ________________________________ Period ______ Date Due _____________________
2. Read the volume of liquid using different glassware, and record the volume using the
correct number of significant figures. Record the volume measurements in these cylinders.
3. Calculate the volume of a regular solid from its dimensions measured with a caliper. A cube of
3
Plexiglas has a side of length 24.5 mm. Find the volume in cm .
4. Determine the average mass for an object from several balances, and report the average using the
appropriate number of significant figures. (masses: 2.01 g., 2.00 g., 2.02 g.).
Name ________________________________ Period ______ Date Due _____________________
5. Interpret a graph of volume and mass for different sized objects of the same substance. On the
attached graph, what is the density of this substance?
6. What is the equation that allows one to convert degrees Fahrenheit to degrees Celsius?
7. Convert 45K to °C. Then covert to K.