General Chemistry Chapter 1 Bowie State University
The distance between carbon atoms in ethylene is 134 picometers. Which of the following expresses that distance in meters?
1.34 x 10^-10
Which of the following correctly expresses 52,030.2 m in scientific notation?
5.20302 × 104 m
3. Select the best statement.
C) Chemical changes always produce substances different from the starting materials.
The density of mercury, the only metal to exist as a liquid at room temperature, is 13.6 g/cm3. What is that density in pounds per cubic inch?
D. 0.491 lb/in^3
The SI prefix mega- (M) means
D. 10^6
Acetic acid boils at 244.2°F. What is its boiling point in degrees Celsius?
D. 117.9 C
During the swing of a frictionless pendulum, what energy form(s) rem
D. Kinetic plus potential energy
Which of the following is not an SI base unit?
D. gram
The SI unit of speed (velocity) is
D. m/s
Given that 1 inch = 2.54 cm, 1 cm3 is equal to
E. 0.0610 in^3
Which of the following is an extensive property of oxygen?
E. Mass
Water vapor is less dense than ice because
E. Molecules in the gas phase have more space between them than in solids
An important aim in much chemical work is to use macroscopic measurements in order to gain an understanding of the microscopic world.
True
The ripening of fruit, once picked, is an example of physical change.
False
A detailed explanation of natural phenomena that is generally accepted and has been extensively tested is called a
theory
Select the answer with the correct number of decimal places for the following sum: 13.914 cm + 243.1 cm + 12.00460 cm =
269.0 cm
A dose of medication was prescribed to be 35 microliters. Which of the following expresses that volume in centiliters?
3.5 x 10^-3 cL
If the density of a certain spherical atomic nucleus is 1.0 × 1014 g cm-3 and its mass is 2.0 × 10- 23 g, what is its radius in cm?
3.6 x 10^-13 cm
The mass of a sample is 550 milligrams. Which of the following expresses that mass in kilograms?
5.5 x 10^-4 kg
The average distance from Earth to the Sun is 150 megameters. What is that distance in meters?
6.1 x105 km
The numerical value of any temperature expressed in Celsius is always different from the numerical value of the same temperature in Fahrenheit.
False
Which of the following correctly shows how to convert a density of 20.1 g cm-3 to units of kg m-3?
(1 cm)^3/(0.01)^3
Which one of the following numbers contains a digit or digits which is/are not significant?
.0043
Which of the following correctly expresses 0.000007913 g in scientific notation?
7.913 × 10^-6 g
Express 96,342 m using 2 significant figures.
96000
Select the best statement.
A) Physical changes may be reversed by changing the temperature.
The result of (3.8621 × 1.5630) - 5.98 is properly written as
A. 0.06
The area of a 15-inch pizza is 176.7 in2. Express this area in square centimeters.
A. 1140 cm^2
Acetone, which is used as a solvent and as a reactant in the manufacture of Plexiglas®, boils at 56.1°C. What is the boiling point in degrees Fahrenheit?
B. 133 F
The appropriate number of significant figures in the result of 15.234 × 15.208 is
B. 2
Talc is a mineral that has low conductivity for heat and electricity and that is not attacked by acid. It is used as talcum powder and face powder. A sample of talc weighs 35.97 g in air and 13.65 g in mineral oil (d = 1.75 g/cm3). What is the density of talc?
B. 2.82 g/cm^3
The speed needed to escape the pull of Earth's gravity is 11.3 km/s. What is this speed in mi/h?
B. 25,300 mi/h
Isopropyl alcohol, commonly known as rubbing alcohol, boils at 82.4°C. What is the boiling point in kelvins?
B. 355.6 K
A dictionary has the following definition for a word: "A tentative explanation that accounts for a set of facts." Which of the following words best fits that definition?
Hypothesis
Write the following numbers and results in standard notation, with appropriate significant figures. a. 7.85 × 10-3 b. 7.85 × 104 c. 5.920 × 103 d. 7.85 × 1012 ÷ 1010 e. 7.00 × 10-5
a. 0.00785 b. 78500 c. 5920. d. 785 e. 0.0000700
Which of the following represents the largest volume?
100 mL
Select the answer that expresses the result of this calculation with the correct number of significant figures and with correct units. 16.18 cm × 9.6114 g ÷ 1.4783 cm2 =
105.2 g/cm
When a wooden match burns in air, chemical potential energy is converted to kinetic energy.
True
When applying the scientific method, a model or theory should be based on experimental data.
True
An evacuated 276 mL glass bulb weighs 129.6375 g. Filled with an unknown gas, the bulb weighs 130.0318 g. Calculate the gas density in g/L, and express it with an appropriate number of significant figures.
1.43 g/L
At a pressure of one billionth (10-9) of atmospheric pressure, there are about 2.7 × 1010 molecules in one cubic centimeter of a gas. How many molecules is this per cubic meter?
A. 2.7 x 10^16
A large pizza has a diameter of 15 inches. Express this diameter in centimeters.
A. 38 cm
The difference between a student's experimental measurement of the density of sodium chloride and the known density of this compound reflects the ___________ of the student's result.
Accuracy
A student makes several measurements of the density of an unknown mineral sample. She then reports the average value of these measurements. The number of significant figures she uses in her result should be a measure of its
B. Precision
The average distance between the Earth and the Moon is 240,000 miles. Express this distance in kilometers.
C. 3.9 x 10^5 km
4. Which of the following is a chemical change?
C. Broiling a steak on a grill
A scientist made careful measurements of the pressure and temperature of many different gases. Based on these measurements, he concluded that "the pressure of a fixed amount of gas, measured at constant volume, is directly proportional to its absolute temperature." This statement is best described as a
Law
The number 6.0448, rounded to 3 decimal places, becomes 6.045.
True