Chemistry 101 Chapter 2 Practice Problems Answer Key
1. Express each of the following numbers in scientific (exponential) notation.
a. 12,500
b. 37,400,000
c. 0.0202
d. 0.0000104
1.25 x 104
3.74 x 107
2.02 x 10-2
1.04 x 10-5
2. Express each of the followi
Chem 111-Worksheet Chapter 6-1
1. Chemical energy is
A) the energy stored within the structural units of chemical substances.
B) the energy associated with the random motion of atoms and molecules.
C) solar energy, i.e. energy that comes from the sun.
D)
1
Lecture Problems CHAPTER 2
Temperature Conversion Problems:
1. The temperature in this room is 26oC, convert to Kelvin.
2. The temperature outside is 333K, convert to Centigrade.
Significant Figures Problems: Give the number of significant figures in ea
MEASUREMENT
Qualitative measurements - the man is tall
Quantitative measurements - the man is 80.5 inches
tall
What Is a Measurement?
Quantitative
observation.
Comparison to an
agreed upon standard.
Every measurement
has a number and a
unit.
Tro's "Int
Graduated Cylinders
Graduated cylinders are the tools commonly used to make
moderately precise measurements of volumes in the laboratory. The volumes can be measured to 3 signicant digits if
care is taken. The cylinders come in a variety of sizes. The
div
Reading a Graduated Cylinder Accurately
Expert Information: A graduated cylinder is used to measure liquid volume. The unit is the
milliliter, abbreviated mL. To use a graduated cylinder, you must remember the following:
Place the graduated cylinder on a
1
Solutions to the Lecture Problems Chapter 3
Classifying Matter Problems
1. Heterogeneous mix
2. compound
3. element
4. homogeneous mix
5. heterogeneous mix
6. element
7. element
8. heterogeneous mix
9. compound
10. homogeneous mix
Type of Change Problem
Key
Review Unit 2
. Rewrite the following in scientiﬁc notation.
a. 433 7.53; >4. M.) 2
b. 1,110,000,000 M / 209
C. Z .62 king“?!
d. 0.000104 J,
/-0‘/ )4 i0
. How many sig ﬁgs are in each of the numbers in question #1?
a, (3) 4.4. (:3) 2.133 01.433
. Rewr
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Chapter 2: Measurement and Problem Solving
UNITS OF MEASUREMENTS:
Observations: Qualitative measurements (the man is tall)
Quantitative measurements (the man is 80.5 inches tall)
Measurements consist of a number and a unit, without the unit the number i
DIMENSIONAL ANALYSIS PROBLEMS
1. A baseball is thrown at a rate of 89.6 miles per hour. What is the speed in meters
per second?
(89.6 Mi/hr)(1 hr/60 min)(1 min/60s)(1.6093km/mi)(1000m/1 km) = 40.1m/s
2. On the planet Bruto, the currency is based on the Bu
Chemistry 101
Chapter 2 Quiz
10 points
1.
(1 pt) A student needs 15.0 mL of ethanol for an experiment. If the density of the
alcohol is 0.789 g/mL, how many grams of alcohol are needed?
2.
(1 point) While driving in Australia, you fill your car with 55 L
1
Chapter 1: The Chemical World
Definition of Chemistry:
Chemistry: It is the study of properties of materials and changes that they undergo. It can be
applied to all aspects of life (e.g., development of pharmaceuticals, leaf color change in fall, etc.).
1
SOLUTIONS TO LECTURE PROBLEMS CHAPTER 2
1. temperature problems
a. 26C + 273 = 299K
b. 333K 273 = 60C
2. number of significant figures
1. 2
2. 4
3. 4
4. 4
5. 1
3.
scientific notation
a. 5.1x103
b. 3.7x10-3
c. 4.300x10-4
d. 4.20000x103
4. multiplication/
Chemistry 101 Chapter 2 Practice Problems Answer Key
1. Express each of the following numbers in scientific (exponential) notation.
a. 1.25 x 104
b. 3.74 x 107
2. Express each of the following as an ordinary decimal number
c. 20,010
d. 0.001997
3. Who is
Significant Figures Worksheet
1. Underline the significant zeros in the following numbers.
5.08_
508_
5.080 X 103_
0.05080_
50800_
2. State the number of significant digits in the following measurements.
0.0025 cm_
0.0551 grams_
25660 ml_
0.341 kg_
20 cal
Chemistry 101 Chapter 2 Homework
1. Express each of the following numbers in scientific (exponential) notation.
a. 12,500_
b. 37,400,000_
c. 0.0202_
d. 0.0000104_
2. Express each of the following as an ordinary decimal number
a. 6.442 x 103 _
b. 5.991 x 1
Extra Dimensional Analysis Problems
1.
An average adult has 6.0L of blood. The Red Cross usually takes one pint of blood from
each donor at a donation. What is the percentage by volume of a persons blood does a
donor give in one donation?
Know: 6.0L blood
Extra Dimensional Analysis Problems
1.
An average adult has 6.0L of blood. The Red Cross usually takes one pint of blood from
each donor at a donation. What is the percentage by volume of a persons blood does a
donor give in one donation?
2. The area of t
General Chemistry 2
Name(s)
Lab 8: Cu Isolation
Class ID
Date
OBJECTIVES
Students can use Ksp to determine product losses in washing steps.
Students use percent yield to determine efficiency of lab procedure.
Students can add reactions in coupled reaction