Chemistry Chapter 1

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

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?

133 degree F

A large pizza has a diameter of 15 inches. Express this diameter in centimeters.

38 cm

Which of the following correctly expresses 52,030.2 m in scientific notation?

5.20302*10^4 m

The mass of a sample is 550 milligrams. Which of the following expresses that mass in kilograms?

5.5*10^-4 kg

The SI unit of speed (velocity) is

m/s

Which of the following is an extensive property of oxygen?

mass

Water vapor is less dense than ice because

molecules in the gas phase have more space between them than in solids.

A detailed explanation of natural phenomena that is generally accepted and has been extensively tested is called a

theory

An important aim in much chemical work is to use macroscopic measurements in order to gain an understanding of the microscopic world. T/F

true

The number 6.0448, rounded to 3 decimal places, becomes 6.045. T/F

true

When a wooden match burns in air, chemical potential energy is converted to kinetic energy. T/F

true

The appropriate number of significant figures in the result of 15.234 × 15.208 is

2

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?

2.7*10^16

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

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

The area of a 15-inch pizza is 176.7 in2. Express this area in square centimeters.

1140 cm^2

Acetic acid boils at 244.2°F. What is its boiling point in degrees Celsius?

117.9 degree C

Which of the following is a chemical change?

broiling a steak on a grill

Which one of the following numbers contains a digit or digits which is/are not significant?

.0043

The result of (3.8621 × 1.5630) - 5.98 is properly written as

0.06

Given that 1 inch = 2.54 cm, 1 cm3 is equal to

0.0610 in^3

Which of the following represents the largest volume?

100 mL

The SI prefix mega- (M) means

10^6

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?

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?

25,300 mi/h

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.

9.6*10^4 m

Select the best statement. A) Physical properties are not valid characteristics for identifying a substance. B) Physical changes alter the composition of the substances involved. C) Physical changes may be reversed by changing the temperature. D) Physical properties are mostly extensive in nature. E) Physical changes are usually accompanied by chemical changes.

Physical changes may be reversed by changing the temperature.

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

Which of the following is not an SI base unit?

gram

Give an example of a physical property and a chemical property of each of the following: oxygen, copper, octane

oxygen gas- chemical property: reaction with sodium physical property: boiling point copper- chemical property: reaction with nitric acid physical property: electrical conductivity octane- chemical property: reaction with oxygen physical property: boiling point

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

precision

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?

0.491 lb/in^3

A dose of medication was prescribed to be 35 microliters. Which of the following expresses that volume in centiliters?

3.5*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*10^-13 cm

Isopropyl alcohol, commonly known as rubbing alcohol, boils at 82.4°C. What is the boiling point in kelvins?

355.6 K

The average distance between the Earth and the Moon is 240,000 miles. Express this distance in kilometers.

6.1*10^5 km

Select the best statement. A) Chemical changes provide the only valid basis for identification of a substance. B) Chemical changes are easily reversed by altering the temperature of the system. C) Chemical changes always produce substances different from the starting materials. D) Chemical changes are associated primarily with extensive properties. E) Chemical changes are accompanied by changes in the total mass of the substances involved.

Chemical changes always produce substances different from the starting materials.

The average distance from Earth to the Sun is 150 megameters. What is that distance in meters?

1.5*10^8 m

The distance between carbon atoms in ethylene is 134 picometers. Which of the following expresses that distance in meters?

1.34*10^-10 m

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

The numerical value of any temperature expressed in Celsius is always different from the numerical value of the same temperature in Fahrenheit. T/F

false

The ripening of fruit, once picked, is an example of physical change. T/F

false

When applying the scientific method, a model or theory should be based on experimental data. T/F

false

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

During the swing of a frictionless pendulum, what energy form(s) remain constant?

kinetic plus potential energy

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