What is the meaning of the number of digits reported in a measured quantity?

A chemist decomposes several samples of carbon monoxide into carbon and oxygen and weighs the resultant elements. The results are shown in the table. a. Do you notice a pattern in these results? Next, the chemist decomposes several samples of hydrogen peroxide into hydrogen and oxygen. The results are shown in the table. b. Do you notice a similarity between these results and those for carbon monoxide in part a? c. Can you formulate a law from your observations in a and b? d. Can you formulate a hypothesis that might explain your law in c?

Complete the table.

Complete the table.

Determine whether each molecular diagram represents a pure substance or a mixture. If it represents a pure substance, classify the substance as an element or a compound. If it represents a mixture, classify the mixture as homogeneous or heterogeneous.

Determine whether each molecular diagram represents a pure substance or a mixture. If it represents a pure substance, classify the substance as an element or a compound. If it represents a mixture, classify the mixture as homogeneous or heterogeneous.

Based on the molecular diagram, classify each change as physical or chemical.

Based on the molecular diagram, classify each change as physical or chemical.

Convert each temperature. a. \(32^{\circ} \mathrm{F}\) to \(^{\circ} \mathrm{C}\) (temperature at which water freezes) b. 77 K to \({ }^{\circ} \mathrm{F}\) (temperature of liquid nitrogen) c. \(-109^{\circ} \mathrm{F}\) to \(^{\circ} \mathrm{C}\) (temperature of dry ice) d. \(98.6^{\circ} \mathrm{F}\) to K (body temperature) Text Transcription: 32^circ F ^circ C ^circ F -109^circ F ^circ C 98.6^circ F

Convert each temperature. a. \(212^{\circ} \mathrm{F}\) to \({ }^{\circ} \mathrm{C}\) (temperature of boiling water at sea level) b. \(22^{\circ} \mathrm{C}\) to K (approximate room temperature) c. 0.00 K to \({ }^{\circ} \mathrm{F}\) (coldest temperature possible, also known as absolute zero) d. 2.735 K to \({ }^{\circ} \mathrm{C}\) (average temperature of the universe as measured from background black body radiation) Text Transcription: 212^circ F ^circ C 22^circ C ^circ F ^circ C

The coldest ground-level temperature ever measured on Earth is \(-128.6^{\circ} \mathrm{F}\), recorded on July 21, 1983, in Antarctica. Convert that temperature to \({ }^{\circ} \mathrm{C}\) and K. Text Transcription: -128.6^circ F ^circ C

The warmest temperature ever measured in the United States is \(134^{\circ} \mathrm{F}\), recorded on July 10, 1913, in Death Valley, California. Convert that temperature to \({ }^{\circ} \mathrm{C}\) and K. Text Transcription: 134^circ F ^circ C

Use the prefix multipliers to express each measurement without exponents. a. \(1.2 \times 10^{-9} \mathrm{m}\) b. \(22 \times 10^{-15} s\) c. \(1.5 \times 10^{9} \mathrm{g}\) d. \(3.5 \times 10^{6} \mathrm{L}\) Text Transcription: 1.2 times 10^-9 m 22 times 10^-15 s 1.5 times 10^9 g 3.5 times 10^6 L

Use prefix multipliers to express each measurement without exponents. a. \(38.8 \times 10^{5} \mathrm{g}\) b. \(55.2 \times 10^{-10} \mathrm{s}\) c. \(23.4 \times 10^{11} \mathrm{m}\) d. \(87.9 \times 10^{-7} \mathrm{L}\) Text Transcription: 38.8 times 10^5 g 55.2 times 10^-10 s 23.4 times 10^11 m 87.9 times 10^-7 L

Use scientific notation to express each quantity with only base units (no prefix multipliers). a. 4.5 ns b. 18 fs c. 128 pm d. \(35 \mu \mathrm{m}\) Text Transcription: 35 mu m

Use scientific notation to express each quantity with only base units (no prefix multipliers). a. \(35 \mu \mathrm{L}\) b. 225 Mm c. 133 Tg d. 1.5 cg Text Transcription: 35 mu L

Complete the table.

Complete the table.

Express the quantity \(556.2 \times 10^{-12} \mathrm{s}\) in each unit. a. ms b. ns c. ps d. fs Text Transcription: 556.2 times 10^-12 s

A new penny has a mass of 2.49 g and a volume of \(0.349 \mathrm{cm}^{3}\). Is the penny made of pure copper? Explain your answer. Text Transcription: 0.349 cm^3

A titanium bicycle frame displaces 0.314 L of water and has a mass of 1.41 kg. What is the density of the titanium in \(\mathrm{g} / \mathrm{cm}^{3}\)? Text Transcription: g/cm^3

Glycerol is a syrupy liquid often used in cosmetics and soaps. A 3.25 L sample of pure glycerol has a mass of \(4.10 \times 10^{3} \mathrm{g}\). What is the density of glycerol in \(\mathrm{g} / \mathrm{cm}^{3}\)? Text Transcription: 4.10 times 10^3 g g/cm^3

Ethylene glycol (antifreeze) has a density of \(1.11 \mathrm{g} / \mathrm{cm}^{3}\). a. What is the mass in g of 417 mL of ethylene glycol? b. What is the volume in L of 4.1 kg of ethylene glycol? Text Transcription: 1.11 g/cm^3

Acetone (nail polish remover) has a density of \(0.7857 \mathrm{g} / \mathrm{cm}^{3}\). a. What is the mass in g of 28.56 mL of acetone? b. What is the volume in mL of 6.54 g of acetone? Text Transcription: 0.7857 g/cm^3

Human fat has a density of \(0.918 \mathrm{g} / \mathrm{cm}^{3}\). How much volume (in \(\mathrm{cm}^{3}\)) is gained by a person who gains 10.0 lb of pure fat? Text Transcription: 0.918 g/cm^3 cm^3

Read each measurement to the correct number of significant figures. Laboratory glassware should always be read from the bottom of the meniscus.

Read each measurement to the correct number of significant figures. Laboratory glassware should always be read from the bottom of the meniscus. Digital balances normally display mass to the correct number of significant figures for that particular balance.

How many significant figures are in each number? a. 0.000312 m b. 312,000 s c. \(3.12 \times 10^{5} \mathrm{km}\) d. 13,127 s e. 2000 Text Transcription: 3.12 times 10^5 km

How many significant figures are in each number? a. 0.1111 s b. 0.007 m c. 108,700 km d. \(1.563300 \times 10^{11} \mathrm{m}\) e. 30,800 Text Transcription: 1.563300 times 10^11 m

Which numbers are exact (and therefore have an unlimited number of significant figures)? a. \(\pi=3.14\) b. 12 in = 1 ft c. EPA gas mileage rating of 26 miles per gallon d. 1 gross = 144 Text Transcription: pi=3.14

Indicate the number of significant figures in each number. If the number is an exact number, indicate an unlimited number of significant figures. a. 325,365,189 (July 4, 2017 U.S. population) b. 2.54 cm = 1 in c. \(11.4 \mathrm{g} / \mathrm{cm}^{3}\) (density of lead) d. 12 = 1 dozen Text Transcription: 11.4 g/cm^3

Round each number to three significant figures. a. 79,845.82 b. \(1.548937 \times 10^{7}\) c. 2.3499999995 d. 0.000045389 Text Transcription: 1.548937 times 10^7

Calculate to the correct number of significant figures. a. \(9.15 \div 4.970\) b. 1.54 x 0.03060 x 0.69 c. \(27.5 \times 1.82 \div 100.04\) d. \(\left(2.290 \times 10^{6}\right) \div\left(6.7 \times 10^{4}\right)\) Text Transcription: 9.15 div 4.970 27.5 times 1.82 div 100.04 (2.290 times 10^6) div (6.7 times 10^4)

Calculate to the correct number of significant figures. a. \(89.3 \times 77.0 \times 0.08\) b. \(\left(5.01 \times 10^{5}\right) \div\left(7.8 \times 10^{2}\right)\) c. \(4.005 \times 74 \times 0.007\) d. \(453 \div 2.031\) Text Transcription: 89.3 times 77.0 times 0.08 (5.01 times 10^5) div (7.8 times 10^2) 4.005 times 74 times 0.007 453 div 2.031

Calculate to the correct number of significant figures. a. \((24.6681 \times 2.38)+332.58\) b. \((85.3-21.489) \div 0.0059\) c. \((512 \div 986.7)+5.44\) d. \(\left[\left(28.7 \times 10^{5}\right) \div 48.533\right]+144.99\) Text Transcription: (24.6681 times 2.38)+332.58 (85.3-21.489) div 0.0059 (512 div 986.7)+5.44 [(28.7 times 10^5) div 48.533]+144.99

Calculate to the correct number of significant figures. a. \(\left[\left(1.7 \times 10^{6}\right) \div\left(2.63 \times 10^{5}\right)\right]+7.33\) b. \((568.99-232.1) \div 5.3\) c. \((9443+45-9.9) \times 8.1 \times 10^{6}\) d. \((3.14 \times 2.4367)-2.34\) Text Transcription: [(1.7 times 10^6) div (2.63 times 10^5)]+7.33 (568.99-232.1) div 5.3 (9443+45-9.9) times 8.1 times 10^6 (3.14 times 2.4367)-2.34

Perform each unit conversion. a. 27.8 L to \(\mathrm{cm}^{3}\) b. 1898 mg to kg c. 198 km to cm Text Transcription: cm^3

Perform each unit conversion. a. 28.9 nm to \(\mu \mathrm{m}\) b. \(1432 \mathrm{cm}^{3}\) to L c. 1211 Tm to Gm Text Transcription: mu m 1432 cm^3

A gas can holds 5.0 gal of gasoline. Express this quantity in \(\mathrm{cm}^{3}\). Text Transcription: cm^3

A house has an area of 195 m2. What is its area in each unit? a. \(\mathrm{km}^{2}\) b. \(\mathrm{dm}^{2}\) c. \(\mathrm{cm}^{2}\) Text Transcription: km^2 dm^2 cm^2

A bedroom has a volume of \(115 \mathrm{m}^{3}\). What is its volume in each unit? a. \(\mathrm{km}^{3}\) b. \(\mathrm{dm}^{3}\) c. \(\mathrm{cm}^{3}\) Text Transcription: 115 m^3 km^3 dm^3 cm^3

The average U.S. farm occupies 435 acres. How many square miles is this? \(\left(1 \text { acre }=43,560 \mathrm{ft}^{2}, 1 \mathrm{mile}=5280 \mathrm{ft}\right)\) Text Transcription: (1 acre =43,560 ft^2, 1 mile =5280 ft)

Total U.S. farmland occupies 954 million acres. How many square miles is this? \(\left(1 \text { acre }=43,560 \mathrm{ft}^{2}, 1 \mathrm{mi}=5280 \mathrm{ft}\right)\). Total U.S. land area is 3.537 million square miles. What percentage of U.S. land is farmland? Text Transcription: (1 acre =43,560 ft^2, 1 mi =5280 ft)

Suppose you design a new thermometer called the X thermometer. On the X scale the boiling point of water is \(130^{\circ} \mathrm{X}\), and the freezing point of water is \(10^{\circ} \mathrm{X}\). At what temperature are the readings on the Fahrenheit and X thermometers the same? Text Transcription: 130^circ X 10^circ X

On a new Jekyll temperature scale, water freezes at \(17^{\circ} \mathrm{J}\) and boils at \(97^{\circ} \mathrm{J}\). On another new temperature scale, the Hyde scale, water freezes at \(0^{\circ} \mathrm{H}\) and boils at \(120^{\circ} \mathrm{H}\). If methyl alcohol boils at \(84^{\circ} \mathrm{H}\), what is its boiling point on the Jekyll scale? Text Transcription: 17^circ J 97^circ J 0^circ H 120^circ H 84^circ H

Force is defined as mass times acceleration. Starting with SI base units, derive a unit for force. Using SI prefixes, suggest a convenient unit for the force resulting from a collision with a 10-ton trailer truck moving at 55 mi per hour and for the force resulting from the collision of a molecule of mass around \(10^{-20} \mathrm{kg}\) moving almost at the speed of light \(\left(3 \times 10^{8} \mathrm{m} / \mathrm{s}\right)\) with the wall of its container. (Assume a 1-second deceleration time for both collisions.) Text Transcription: 10^-20 kg (3 times 10^8 m/s)

A temperature measurement of \(25^{\circ} \mathrm{C}\) has three significant figures, while a temperature measurement of \(-196^{\circ} \mathrm{C}\) has only two significant figures. Explain. Text Transcription: 25^circ C -196^circ C

Do each calculation without your calculator and give the answers to the correct number of significant figures. a. \(1.76 \times 10^{-3} / 8.0 \times 10^{2}\) b. \(1.87 \times 10^{-2}+2 \times 10^{-4}-3.0 \times 10^{-3}\) c. \(\left[\left(1.36 \times 10^{5}\right)(0.000322) / 0.082\right](129.2)\) Text Transcription: 1.76 times 10^-3 / 8.0 times 10^2 1.87 \times 10^-2 +2 times 10^-4 -3.0 times 10^-3 [(1.36 times 10^5)(0.000322) / 0.082](129.2)

A thief uses a can of sand to replace a solid gold cylinder that sits on a weight-sensitive, alarmed pedestal. The can of sand and the gold cylinder have exactly the same dimensions (length = 22 and radius = 3.8 cm). a. Calculate the mass of each cylinder (ignore the mass of the can itself). \(\text { (density of gold }=19.3 \mathrm{~g} / \mathrm{cm}^{3} \text {, density of sand } \left.=3.00 \mathrm{~g} / \mathrm{cm}^{3}\right)\) b. Does the thief set off the alarm? Explain. Text Transcription: (density of gold =19.3 g/cm^3, density of sand = 3.00 g /cm^3)

The proton has a radius of approximately \(1.0 \times 10^{-13} \mathrm{cm}\) and a mass of \(1.7 \times 10^{-24} \mathrm{g}\). Determine the density of a proton. For a sphere, \(V=(4 / 3) \pi r^{3}\). Text Transcription: 1.0 times 10^-13 cm 1.7 times 10^-24 g V=(4 / 3) pi r^3

The density of titanium is \(4.51 \mathrm{g} / \mathrm{cm}^{3}\). What is the volume (in cubic inches) of 3.5 lb of titanium? Text Transcription: 4.51 g/cm^3

The density of iron is \(7.86 \mathrm{g} / \mathrm{cm}^{3}\). What is its density in pounds per cubic inch \(\left(\mathrm{lb} / \mathrm{in}^{3}\right)\)? Text Transcription: 7.86 g/cm^3 (lb/in^3)

A steel cylinder has a length of 2.16 in, a radius of 0.22 in, and a mass of 41 g. What is the density of the steel in \(\mathrm{g} / \mathrm{cm}^{3}\)? Text Transcription: g/cm^3

A backyard swimming pool holds 185 cubic yards \(\left(y^{3}\right)\) of water. What is the mass of the water in pounds? Text Transcription: (y^3)

An iceberg has a volume of \(7655 \mathrm{ft}^{2}\). What is the mass of the ice (in kg) composing the iceberg (at \(0^{\circ} \mathrm{C}\))? Text Transcription: 7655 ft^2 0^circ C

The single proton that forms the nucleus of the hydrogen atom has a radius of approximately \91.0 \times 10^{-13} \mathrm{cm}\). The hydrogen atom itself has a radius of approximately 52.9 pm. What fraction of the space within the atom is occupied by the nucleus? Text Transcription: 1.0 times 10^-13 cm

A sample of gaseous neon atoms at atmospheric pressure and \(0^{\circ} \mathrm{C}\) contains \(2.69 \times 10^{22}\) atoms per liter. The atomic radius of neon is 69 pm. What fraction of the space do the atoms themselves occupy? What does this reveal about the separation between atoms in the gaseous phase? Text Transcription: 0^circ C 2.69 times 10^22

The diameter of a hydrogen atom is 212 pm. Find the length in kilometers of a row of \(6.02 \times 10^{23}\) hydrogen atoms. The diameter of a ping pong ball is 4.0 cm. Find the length in kilometers of a row of \(6.02 \times 10^{23}\) ping pong balls. Text Transcription: 6.02 times 10^23 6.02 times 10^23

A length of #8 copper wire (radius = 1.63 mm) has a mass of 24.0 kg and a resistance of 2.061 ohm per km \((\Omega / \mathrm{km})\). What is the overall resistance of the wire? Text Transcription: (Omega /km)

Liquid nitrogen has a density of 0.808 g/mL and boils at 77 K. Researchers often purchase liquid nitrogen in insulated 175 L tanks. The liquid vaporizes quickly to gaseous nitrogen (which has a density of 1.15 g/L at room temperature and atmospheric pressure) when the liquid is removed from the tank. Suppose that all 175 L of liquid nitrogen in a tank accidentally vaporized in a lab that measured \(10.00 \mathrm{m} \times 10.00 \mathrm{m} \times 2.50 \mathrm{m}\). What maximum fraction of the air in the room could be displaced by the gaseous nitrogen? Text Transcription: 10.00 m times 10.00 m times 2.50 m

Mercury is often used in thermometers. The mercury sits in a bulb on the bottom of the thermometer and rises up a thin capillary as the temperature rises. Suppose a mercury thermometer contains 3.380 g of mercury and has a capillary that is 0.200 mm in diameter. How far does the mercury rise in the capillary when the temperature changes from \(0.0^{\circ} \mathrm{C}\) to \(25.0^{\circ} \mathrm{C}\)? The density of mercury at these temperatures is \(13.596 \mathrm{g} / \mathrm{cm}^{3}\) and \(13.534 \mathrm{g} / \mathrm{cm}^{3}\), respectively. Text Transcription: 0.0^circ C 25.0^circ C 13.596 g/cm^3 13.534 g/cm^3

A force of \(2.31 \times 10^{4} \mathrm{N}\) is applied to a diver’s face mask that has an area of \(125 \mathrm{cm}^{2}\). Find the pressure in atm on the face mask. Text Transcription: 2.31 times 10^4 N 125 cm^2

The SI unit of force is the newton, derived from the base units by using the definition of force, F = ma. The dyne is a non-SI unit of force in which mass is measured in grams and time is measured in seconds. The relationship between the two units is \(1 \text { dyne }=10^{-5} \mathrm{N}\). Find the unit of length used to define the dyne. Text Transcription: 1 dyne =10^-5 N

Kinetic energy can be defined as \(\frac{1}{2} m v^{2}\) or as \(\frac{3}{2} P V\). Show that the derived SI units of each of these terms are those of energy. (Pressure is force/area and force is mass : acceleration.) Text Transcription: 1/2 m v^2 3/2 P V

In 1999, scientists discovered a new class of black holes with masses 100 to 10,000 times the mass of our sun that occupy less space than our moon. Suppose that one of these black holes has a mass of \(1 \times 10^{3}\) suns and a radius equal to one-half the radius of our moon. What is the density of the black hole in \(\mathrm{g} / \mathrm{cm}^{3}\)? The radius of our sun is \(7.0 \times 10^{5} \mathrm{km}\), and it has an average density of \(1.4 \times 10^{3} \mathrm{kg} / \mathrm{m}^{3}\). The diameter of the moon is \(2.16 \times 10^{3} \mathrm{mi}\). Text Transcription: 1 times 10^3 g/cm^3 7.0 times 10^5 km 1.4 times 10^3 kg/m^3 2.16 times 10^3 mi

Suppose that polluted air has carbon monoxide (CO) levels of 15.0 ppm. An average human inhales about 0.50 L of air per breath and takes about 20 breaths per minute. How many milligrams of carbon monoxide does the average person inhale in an 8-hour period at this level of carbon monoxide pollution? Assume that the carbon monoxide has a density of 1.2 g/L. (Hint: 15.0 ppm CO means 15.0 L CO per \(10^{6} \mathrm{L}\) air.) Text Transcription: 10^6 L

Approximate the percent increase in waist size that occurs when a 155-lb person gains 40.0 lb of fat. Assume that the volume of the person can be modeled by a cylinder that is 4.0 ft tall. The average density of a human is about \(1.0 \mathrm{g} / \mathrm{cm}^{3}\), and the density of fat is \(0.918 \mathrm{g} / \mathrm{cm}^{3}\). Text Transcription: 1.0 g/cm^3 0.918 g/cm^3

A box contains a mixture of small copper spheres and small lead spheres. The total volume of both metals is measured by the displacement of water to be \(427 \mathrm{cm}^{3}\), and the total mass is 4.36 kg. What percentage of the spheres are copper? Text Transcription: 427 cm^3

The diagram shown first represents solid carbon dioxide, also known as dry ice. Which of the other diagrams best represents the dry ice after it has sublimed into a gas?

Substance A has a density of \(1.7 \mathrm{g} / \mathrm{cm}^{3}\). Substance B has a density of \(1.7 \mathrm{g} / \mathrm{cm}^{3}\). Without doing any calculations, determine which substance is more dense. Text Transcription: 1.7 g/cm^3 1.7 g/cm^3

For each box, examine the blocks attached to the balances. Based on their positions and sizes, determine which block is more dense (the dark block or the lighter-colored block), or if the relative densities cannot be determined. (Think carefully about the information being shown.)

One inch is equal to 2.54 cm. Draw a line that is 1 in long, and mark the centimeters on the line. Draw a cube that is 1 in on each side. Draw lines on each face of the cube that are 1 cm apart. How many cubic centimeters are there in \(1 \mathrm{in}^{3}\)? Text Transcription: 1 in^3

The density of a substance can change with temperature. The graph that follows displays the density of water from \(-150^{\circ} \mathrm{C}\) to \(100^{\circ} \mathrm{C}\). Examine the graph and answer the questions. a. Water undergoes a large change in density at \(0^{\circ} \mathrm{C}\) as it freezes to form ice. Calculate the percent change in density that occurs when liquid water freezes to ice at \(0^{\circ} \mathrm{C}\). \(\left(\text { Hint: } \% \text { change }=\frac{\text { final value }-\text { initial value }}{\text { initial value }} \times 100 \%\right)\) b. Calculate the volume \(\left(\text { in } \mathrm{cm}^{3}\right)\) of 54 g of water at \(1^{\circ} \mathrm{C}\) and the volume of the same mass of ice at \(-1^{\circ} \mathrm{C}\). What is the change in volume? c. Antarctica contains 26.5 million cubic kilometers of ice. Assume the temperature of the ice is \(-20^{\circ} \mathrm{C}\). If all of this ice were heated to \(1^{\circ} \mathrm{C}\) and melted to form water, what volume of liquid water would form? d. A 1.00-L sample of water is heated from \(1^{\circ} \mathrm{C}\) to \(100^{\circ} \mathrm{C}\). What is the volume of the water after it is heated? Text Transcription: -150^circ C 100^circ C 0^circ C 0^circ C (Hint: % change = frac final value - initial value / initial value times 100%) (in cm^3) 1^circ C -1^circ C -20^circ C 1^circ C 1^circ C 100^circ C

Explain this statement in your own words and give an example. The properties of the substances around us depend on the atoms and molecules that compose them.

Explain the main goal of chemistry.

Describe the scientific approach to knowledge. How does it differ from other approaches?

Explain the differences between a hypothesis, a law, and a theory.

What observations did Antoine Lavoisier make? What law did he formulate?

What theory did John Dalton formulate?

What is wrong with the expression “That is just a theory,” if by theory the speaker is referring to a scientific theory?

What are two different ways to classify matter?

How do solids, liquids, and gases differ?

What is the difference between a crystalline solid and an amorphous solid?

Explain the difference between a pure substance and a mixture.

Explain the difference between an element and a compound.

Explain the difference between a homogeneous and a heterogeneous mixture.

What kind of mixtures can be separated by filtration?

Explain how distillation is used to separate mixtures.

What is the difference between a physical property and a chemical property?

What is the difference between a physical change and a chemical change? List some examples of each.

Explain the significance of the law of conservation of energy.

What kind of energy is chemical energy? In what way is an elevated weight similar to a tank of gasoline?

What are the standard SI base units of length, mass, time, and temperature?

What are the three common temperature scales? Does the size of a degree differ among them?

What are prefix multipliers? List some examples.

What is a derived unit? List an example.

Explain the difference between density and mass.

Explain the difference between intensive and extensive properties.

What is the meaning of the number of digits reported in a measured quantity?

When multiplying or dividing measured quantities, what determines the number of significant figures in the result?

When adding or subtracting measured quantities, what determines the number of significant figures in the result?

What are the rules for rounding off the results of calculations?

Explain the difference between precision and accuracy.

Explain the difference between random error and systematic error.

What is dimensional analysis?

Classify each statement as an observation, a law, or a theory. a. All matter is made of tiny, indestructible particles called atoms. b. When iron rusts in a closed container, the mass of the container and its contents does not change. c. In chemical reactions, matter is neither created nor destroyed. d. When a match burns, heat is released.

Classify each statement as an observation, a law, or a theory. a. Chlorine is a highly reactive gas. b. If elements are listed in order of increasing mass of their atoms, their chemical reactivities follow a repeating pattern. c. Neon is an inert (or nonreactive) gas. d. The reactivity of elements depends on the arrangement of their electrons.

When astronomers observe distant galaxies, they can tell that most of them are moving away from one another. In addition, the more distant the galaxies, the more rapidly they are likely to be moving away from each other. Can you devise a hypothesis to explain these observations?

Classify each substance as a pure substance or a mixture. If it is a pure substance, classify it as an element or a compound. If it is a mixture, classify it as homogeneous or heterogeneous. a. sweat b. carbon dioxide c. aluminum d. vegetable soup

Classify each substance as a pure substance or a mixture. If it is a pure substance, classify it as an element or a compound. If it is a mixture, classify it as homogeneous or heterogeneous. a. wine b. beef stew c. iron d. carbon monoxide

Classify each of the listed properties of isopropyl alcohol (also known as rubbing alcohol) as physical or chemical. a. colorless b. flammable c. liquid at room temperature d. density = 0.79 g>mL e. mixes with water

Classify each of the listed properties of ozone (a pollutant in the lower atmosphere but part of a protective shield against UV light in the upper atmosphere) as physical or chemical. a. bluish color b. pungent odor c. very reactive d. decomposes on exposure to ultraviolet light e. gas at room temperature

Classify each property as physical or chemical. a. the tendency of ethyl alcohol to burn b. the shine on silver c. the odor of paint thinner d. the flammability of propane gas

Classify each property as physical or chemical. a. the boiling point of ethyl alcohol b. the temperature at which dry ice evaporates c. the tendency of iron to rust d. the color of gold

Classify each change as physical or chemical. a. Natural gas burns in a stove. b. The liquid propane in a gas grill evaporates because the valve was left open. c. The liquid propane in a gas grill burns in a flame. d. A bicycle frame rusts on repeated exposure to air and water.

Classify each change as physical or chemical. a. Sugar burns when heated in a skillet. b. Sugar dissolves in water. c. A platinum ring becomes dull because of continued abrasion. d. A silver surface becomes tarnished after exposure to air for a long period of time.

Express the quantity 254,998 m in each unit. a. km b. Mm c. mm d. cm

How many 1-cm squares would it take to construct a square that is 1 m on each side?

How many 1-cm cubes would it take to construct a cube that is 4 cm on edge?

A supposedly gold nugget displaces 19.3 mL of water and has a mass of 371 g. Could the nugget be made of gold?

A small airplane takes on 245 L of fuel. If the density of the fuel is 0.821 g/mL, what mass of fuel has the airplane taken on?

For each number, underline the zeroes that are significant and draw an x through the zeroes that are not. a. 1,050,501 km b. 0.0020 m c. 0.000000000000002 s d. 0.001090 cm

For each number, underline the zeroes that are significant and draw an x through the zeroes that are not. a. 180,701 mi b. 0.001040 m c. 0.005710 km d. 90,201 m

Round each number to four significant figures. a. 156.852 b. 156.842 c. 156.849 d. 156.899

Calculate to the correct number of significant figures. a. 43.7 - 2.341 b. 17.6 + 2.838 + 2.3 + 110.77 c. 19.6 + 58.33 - 4.974 d. 5.99 - 5.572

Calculate to the correct number of significant figures. a. 0.004 + 0.09879 b. 1239.3 + 9.73 + 3.42 c. 2.4 - 1.777 d. 532 + 7.3 - 48.523

A flask containing 11.7 mL of a liquid weighs 132.8 g with the liquid in the flask and 124.1 g when empty. Calculate the density of the liquid in g/mL to the correct number of significant digits.

A flask containing 9.55 mL of a liquid weighs 157.2 g with the liquid in the flask and 148.4 g when empty. Calculate the density of the liquid in g/mL to the correct number of significant digits.

Perform each unit conversion. a. 154 cm to in b. 3.14 kg to g c. 3.5 L to qt d. 109 mm to in

Perform each unit conversion. a. 1.4 in to mm b. 116 ft to cm c. 1845 kg to lb d. 815 yd to km

A runner wants to run 10.0 km. Her running pace is 7.5 mi per hour. How many minutes must she run?

A cyclist rides at an average speed of 18 mi per hour. If she wants to bike 212 km, how long (in hours) must she ride?

A certain European automobile has a gas mileage of 17 km/L. What is the gas mileage in miles per gallon?

An acetaminophen suspension for infants contains 80 mg/0.80 mL suspension. The recommended dose is 15 mg/kg body weight. How many mL of this suspension should be given to an infant weighing 14 lb? (Assume two significant figures.)

An ibuprofen suspension for infants contains 100 mg/5.0 mL suspension. The recommended dose is 10 mg/kg body weight. How many mL of this suspension should be given to an infant weighing 18 lb? (Assume two significant figures.)

There are exactly 60 seconds in a minute, exactly 60 minutes in an hour, exactly 24 hours in a mean solar day, and 365.24 solar days in a solar year. How many seconds are in a solar year? Give your answer with the correct number of significant figures.

Determine the number of picoseconds in 2.0 hours.

Classify each property as intensive or extensive. a. volume b. boiling point c. temperature d. electrical conductivity e. energy

At what temperatures are the readings on the Fahrenheit and Celsius thermometers the same?

The value of the euro was recently $1.15 U.S., and the price of 1 liter of gasoline in France is 1.42 euro. What is the price of 1 gallon of gasoline in U.S. dollars in France?

A solid aluminum sphere has a mass of 85 g. Use the density of aluminum to find the radius of the sphere in inches.

The Toyota Prius, a hybrid electric vehicle, has an EPA gas mileage rating of 52 mi/gal in the city. How many kilometers can the Prius travel on 15 L of gasoline?

The Honda Insight, a hybrid electric vehicle, has an EPA gas mileage rating of 41 mi/gal in the city. How many kilometers can the Insight travel on the amount of gasoline that would fit in a soda can? The volume of a soda can is 355 mL.

The world record in the men’s 100-m dash is 9.58 s, and in the 100-yd dash it is 9.07 s. Find the speed in mi/hr of the runners who set these records. (Assume three significant figures for 100 m and 100 yd.)

Table salt contains 39.33 g of sodium per 100 g of salt. The U.S. Food and Drug Administration (FDA) recommends that adults consume less than 2.40 g of sodium per day. A particular snack mix contains 1.25 g of salt per 100 g of the mix. What mass of the snack mix can an adult consume and still be within the FDA limit? (Assume three significant figures for 100 g.)

Lead metal can be extracted from a mineral called galena, which contains 86.6% lead by mass. A particular ore contains 68.5% galena by mass. If the lead can be extracted with 92.5% efficiency, what mass of ore is required to make a lead sphere with a 5.00-cm radius?

Rolls of aluminum foil are 304 mm wide and 0.016 mm thick. What maximum length of aluminum foil can be made from 1.10 kg of aluminum?

Nanotechnology, the field of building ultrasmall structures one atom at a time, has progressed in recent years. One potential application of nanotechnology is the construction of artificial cells. The simplest cells would probably mimic red blood cells, the body’s oxygen transporters. Nanocontainers, perhaps constructed of carbon, could be pumped full of oxygen and injected into a person’s bloodstream. If the person needed additional oxygen—due to a heart attack perhaps, or for the purpose of space travel—these containers could slowly release oxygen into the blood, allowing tissues that would otherwise die to remain alive. Suppose that the nanocontainers were cubic and had an edge length of 25 nm. a. What is the volume of one nanocontainer? (Ignore the thickness of the nanocontainer’s wall.) b. Suppose that each nanocontainer could contain pure oxygen pressurized to a density of 85 g/L. How many grams of oxygen could each nanocontainer contain? c. Air typically contains about 0.28 g of oxygen per liter. An average human inhales about 0.50 L of air per breath and takes about 20 breaths per minute. How many grams of oxygen does a human inhale per hour? (Assume two significant figures.) d. What is the minimum number of nanocontainers that a person would need in his or her bloodstream to provide 1 hour’s worth of oxygen? e. What is the minimum volume occupied by the number of nanocontainers calculated in part d? Is such a volume feasible, given that total blood volume in an adult is about 5 L?

A volatile liquid (one that easily evaporates) is put into a jar, and the jar is then sealed. Does the mass of the sealed jar and its contents change upon the vaporization of the liquid?

A cube has an edge length of 7 cm. If it is divided into 1-cm cubes, how many 1-cm cubes are there?

Let a triangle represent atoms of element A and a circle represent atoms of element B. a. Draw an atomic-level view of a homogeneous mixture of elements A and B. b. Draw an atomic view of the compound AB in a liquid state (molecules close together). c. Draw an atomic view of the compound AB after it has undergone a physical change (such as evaporation). d. Draw an atomic view of the compound after it has undergone a chemical change (such as decomposition of AB into A and B).

Identify each statement as being most like an observation, a law, or a theory. a. All coastal areas experience two high tides and two low tides each day. b. The tides in Earth’s oceans are caused mainly by the gravitational attraction of the moon. c. Yesterday, high tide in San Francisco Bay occurred at 2:43 a.m. and 3:07 p.m. d. Tides are higher at the full moon and new moon than at other times of the month.

Using white and black circles to represent different kinds of atoms, make a drawing that accurately represents each sample of matter: a solid element, a liquid compound, and a heterogeneous mixture. Make a drawing (clearly showing before and after) depicting your liquid compound undergoing a physical change. Make a drawing depicting your solid element undergoing a chemical change.

Look up the measurement of the approximate thickness of a human hair. a. Convert the measurement to an SI unit (if it isn’t already). b. Write it in scientific notation. c. Write it without scientific notation. d. Write it with an appropriate prefix on a base unit. Now repeat these steps using the distance from Earth to the sun.

The following statements are all true. a. Jessica’s house is 5 km from the grocery store. b. Jessica’s house is 4.73 km from the grocery store. c. Jessica’s house is 4.73297 km from the grocery store. How can all the statements be true? What does the number of digits in each statement communicate? What sort of device would Jessica need to make the measurement in each statement?

Convert the height of each member in your group from feet and inches to meters. Once you have your heights in meters, calculate the sum of all the heights. Use appropriate rules for significant figures at each step.