Problem 1

A Create a table that describes the three common states of matter in

terms of their shape, volume, and compressibilit

Janos S.

Numerade Educator

Problem 2

Describe the characteristics that identify a sample of matter as a substance.

Linhan Y.

Numerade Educator

Problem 3

Classify each of the following as a physical or a chemical proper

\begin{equation}

\begin{array}{l}{\text { a. Iron and oxygen form rust. }} \\ {\text { b. Iron is more dense than aluminum. }} \\ {\text { c. Magnesium burns brightly when ignited. }} \\ {\text { d. Oil and water do not mix. }} \\ {\text { e. Mercury melts at }-39^{\circ} \mathrm{C} \text { . }}\end{array}

\end{equation}

Janos S.

Numerade Educator

Problem 4

Organize Create a chart that compares physical and chemical properties. Give

two examples for each type of proper.

Ali M.

Numerade Educator

Problem 5

Use the data in the table to answer the following questions.

How many grams of bromine reacted? How many grams of compound were formed?

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Problem 6

From a laboratory process designed to separate water into hydrogen and oxygen gas,

a student collected 10.0 g of hydrogen and 79.4 g of oxygen. How much water was

originally involved in the process?

Linhan Y.

Numerade Educator

Problem 7

A student carefully placed 15.6 g of sodium in a reactor supplied with an excess quantity

of chlorine gas. When the reaction was complete, the student obtained 39.7 g of sodium

chloride. Calculate how many grams of chlorine gas reacted. How many grams of

sodium reacted?

Janos S.

Numerade Educator

Problem 8

A 10.0-g sample of magnesium reacts with oxygen to form 16.6 g of magnesium oxide.

How many grams of oxygen reacted?

Linhan Y.

Numerade Educator

Problem 9

Challenge 106.5 g of HCl(g) react with an unknown amount of $\mathrm{NH}_{3}(\mathrm{g})$ to produce 157.5 $\mathrm{g}$ of $\mathrm{NH}_{4} \mathrm{Cl}(\mathrm{s})$ . How many grams of $\mathrm{NH}_{3}(\mathrm{g})$ reacted? Is the law of conservation of

mass observed in the reaction? Justify your answer.

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Problem 10

A Classify each example as a physical change or a chemical change.

\begin{equation}

\begin{array}{l}{\text { a. crushing an aluminum can }} \\ {\text { b. recycling used aluminum cans to make new aluminum cans }} \\ {\text { c. aluminum combining with oxygen to form aluminum oxide }}\end{array}

\end{equation}

Linhan Y.

Numerade Educator

Problem 11

Describe the results of a physical change and list three examples of physical

change.

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Problem 12

Describe the results of a chemical change. List four indicators of chemical

change.

Linhan Y.

Numerade Educator

Problem 13

Calculate Solve each of the following.

\begin{equation}

\begin{array}{l}{\text { a. In the complete reaction of } 22.99 \mathrm{g} \text { of sodium with } 35.45 \mathrm{g} \text { of chlorine, what }} \\ {\text { mass of sodium chloride is formed? }}\end{array}

\end{equation}

\begin{equation}

\begin{array}{l}{\text { b. } A 12.2 \text { -g sample of } X \text { reacts with a sample of } Y \text { to form } 78.9 \text { g of } X Y . \text { What }} \\ {\text { is the mass of } Y \text { that reacted? }}\end{array}

\end{equation}

Janos S.

Numerade Educator

Problem 14

Evaluate A friend tells you, "Because composition does not change

during a physical change, the appearance of a substance does not change."

Is your friend correct? Explain.

Linhan Y.

Numerade Educator

Problem 15

A Classify each of the following as either a heterogeneous or a

homogeneous mixture.

a. tap water $\quad$ b. air $\quad$ c. raisin muffin

Janos S.

Numerade Educator

Problem 17

Describe the separation technique that could be used to separate each of the

following mixture.

\begin{equation}

\begin{array}{l}{\text { a. two colorless liquids }} \\ {\text { b. a nondissolving solid mixed with a liquid }} \\ {\text { c. red and blue marbles of the same size and mass }}\end{array}

\end{equation}

Janos S.

Numerade Educator

Problem 18

Design a concept map that summarizes the relationships among matter,

elements, mixtures, compounds, pure substances, homogeneous mixtures, and

heterogeneous mixtures.

Linhan Y.

Numerade Educator

Problem 19

A 78.0 -g sample of an unknown compound contains 12.4 g of

hydrogen. What is the percent by mass of hydrogen in the compound?

Janos S.

Numerade Educator

Problem 20

1.0 $\mathrm{g}$ of hydrogen reacts completely with 19.0 $\mathrm{g}$ of fluorine. What is the

percent by mass of hydrogen in the compound that is formed?

Linhan Y.

Numerade Educator

Problem 21

If 3.5 $\mathrm{g}$ of element $\mathrm{X}$ reacts with 10.5 $\mathrm{g}$ of element $\mathrm{Y}$ to form the

compound $\mathrm{XY},$ what is the percent by mass of element $\mathrm{X}$ in the

compound? The percent by mass of element $\mathrm{Y}$ ?

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Problem 22

Two unknown compounds are tested. Compound I contains 15.0 $\mathrm{g}$ of

hydrogen and 120.0 g of oxygen. Compound II contains 2.0 $\mathrm{g}$ of

hydrogen and 32.0 $\mathrm{g}$ of oxygen. Are the compounds the same? Explain

your answer.

Linhan Y.

Numerade Educator

Problem 23

Challenge All you know about two unknown compounds is that they

have the same percent by mass of carbon. With only this information,

can you be sure the two compounds are the same? Explain.

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Problem 25

Describe the basic organizational feature of the periodic table of the elements.

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Problem 27

State the type of compounds that are compared in the law of multiple

proportions.

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Problem 28

Complete the table, and then analyze the datat to determine if Compounds I

and ll are the same compound. If the compounds are different, use the law of

multiple proportions to show the relationship between them.

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Problem 29

Calculate the mass percent of hydrogen in water and the mass percent of

oxygen in water.

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Problem 34

Identify each physical property as extensive or intensive.

\begin{equation}

\begin{array}{ll}{\text { a. melting point }} & {\text { c. density }} \\ {\text { b. mass }} & {\text { d. length }}\end{array}

\end{equation}

Linhan Y.

Numerade Educator

Problem 35

"Properties are not affected by changes in temperature

and pressure." Is this statement true or false? Explain.

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Problem 36

List the three states of matter, and give an example for

each state. Differentiate between a gas and a vapor.

Linhan Y.

Numerade Educator

Problem 37

Classify each as either a solid, a liquid, or a gas at room temperature.

\begin{equation}

\begin{array}{ll}{\text { a. milk }} & {\text { d. helium }} \\ {\text { b. air }} & {\text { e. diamond }} \\ {\text { c. copper }} & {\text { f. candle wax }}\end{array}

\end{equation}

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Problem 38

Classify each as a physical property or a chemical property.

\begin{equation}

\begin{array}{l}{\text { a. Aluminum has a silvery color. }} \\ {\text { b. Gold has a density of 19 } \mathrm{g} / \mathrm{cm}^{3} \text { . }} \\ {\text { c. Sodium ignites when dropped in water. }}\end{array}

\end{equation}

\begin{equation}

\begin{array}{l}{\text { d. Water boils at } 100^{\circ} \mathrm{C} \text { . }} \\ {\text { e. Silver tarnishes. }} \\ {\text { f. Mercury is a liquid at room temperature. }}\end{array}

\end{equation}

Linhan Y.

Numerade Educator

Problem 39

A carton of milk is poured into a bowl. Describe the

changes that occur in the milks shape and volume.

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Problem 40

Boiling Water At what temperature would 250 $\mathrm{mL}$ of

water boil? 1000 $\mathrm{mL}$ ? Is the boiling point an intensive or

extensive property? Explain.

Linhan Y.

Numerade Educator

Problem 41

Chemical Analysis A scientist wants to identify an

unknown compound on the basis of its physical properties. The substance is a white solid at room temperature. Attempts to determine its boiling point were unsuccessful. Using Table 3.6, name the unknown compound.

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Problem 42

Label each set of diagrams in Figure 3.22 as a physical

or a chemical change.

Linhan Y.

Numerade Educator

Problem 43

Classify each as a physical change or a chemical change.

\begin{equation}

\begin{array}{l}{\text { a. breaking a pencil in two }} \\ {\text { b. water freezing and forming ice }} \\ {\text { c. frying an egg }} \\ {\text { d. burning wood }} \\ {\text { e. leaves changing colors in the fall }}\end{array}

\end{equation}

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Problem 44

Ripening Is the process of bananas ripening a chemical

change or a physical change? Explain.

Linhan Y.

Numerade Educator

Problem 46

List four indicators that a chemical change has probably occured.

Linhan Y.

Numerade Educator

Problem 47

Rust Iron and oxygen combine to form iron oxide, or

rust. List the reactants and products of this reaction.

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Problem 48

Burning Candle After burning for three hours, a candle has lost half of its mass. Explain why this example

does not violate the law of conservation of mass.

Linhan Y.

Numerade Educator

Problem 50

Ammonia Production $\mathrm{A} 28.0$ -g sample of nitrogen gas

combines completely with 6.0 $\mathrm{g}$ of hydrogen gas to form

ammonia. What is the mass of ammonia formed?

Linhan Y.

Numerade Educator

Problem 51

A 13.0 -g sample of X combines with a $34.0-\mathrm{g}$ sample of

$\mathrm{Y}$ to form the compound $\mathrm{XY}_{2} .$ What is the mass of the

reactants?

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Problem 52

If 45.98 $\mathrm{g}$ of sodium combines with an excess of chlorine

gas to form 116.89 $\mathrm{g}$ of sodium chloride, what mass of

chlorine gas is used in the reaction?

Linhan Y.

Numerade Educator

Problem 53

A substance breaks down into its component elements

when it is heated. If 68.0 g of the substance is present

before it is heated, what is the combined mass of the

component elements after heating?

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Problem 54

Copper sulfide is formed when copper and sulfur are

heated together. In this reaction, 127 $\mathrm{g}$ of copper reacts

with 41 $\mathrm{g}$ of sulfur. After the reaction is complete, 9 $\mathrm{g}$ of

sulfur remains unreacted. What is the mass of copper

sulfide formed?

Linhan Y.

Numerade Educator

Problem 55

When burning 180 of glucose in the presence of

192 of oxygen, water and carbon dioxide are

produced. If 108 gof water is produced, how much

carbon dioxide is produced?

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Problem 58

Describe a method that could be used to separate each mixture.

\begin{equation}

\begin{array}{ll}{\text { a. iron filings and sand }} & {\text { c. the components of ink }} \\ {\text { b. sand and salt }} & {\text { d. helium and oxygen gases }}\end{array}

\end{equation}

Linhan Y.

Numerade Educator

Problem 59

"A mixture is the chemical bonding of two or more sub-

stances in any proportion." Is this statement true or

false? Explain.

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Problem 60

Which of the following are the same and which are different?

\begin{equation}

\begin{array}{l}{\text { a. a substance and a pure substance }} \\ {\text { b. a heterogeneous mixture and a solution }} \\ {\text { c. a substance and a mixture }} \\ {\text { d. a homogeneous mixture and a solution }}\end{array}

\end{equation}

Linhan Y.

Numerade Educator

Problem 61

Describe how a homogeneous mixture differs from a heterogeneous mixture.

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Problem 62

Seawater is composed of salt, sand, and water. Is seawater a heterogeneous or homogeneous mixture? Explain.

Linhan Y.

Numerade Educator

Problem 63

Iced Tea Use iced tea with and without ice cubes as

examples to explain homogeneous and heterogeneous

mixtures. If you allow all of the ice cubes to melt, what

type of mixture remains?

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Problem 66

Correct the following statements.

\begin{equation}

\begin{array}{l}{\text { a. An element is a combination of two or more }} \\ {\text { compounds. }} \\ {\text { b. When a small amount of sugar is completely dissolved }} \\ {\text { in water, a heterogeneous solution is formed. }}\end{array}

\end{equation}

Linhan Y.

Numerade Educator

Problem 67

Name the elements contained in the following compounds.

\begin{equation}

\begin{array}{ll}{\text { a. sodium chloride }(\mathrm{NaCl})} & {\text { c. ethanol }\left(\mathrm{C}_{2} \mathrm{H}_{6} \mathrm{O}\right)} \\ {\text { b. ammonia }\left(\mathrm{NH}_{3}\right)} & {\mathrm{d} \text { bromine }\left(\mathrm{Br}_{2}\right)}\end{array}

\end{equation}

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Problem 68

What was Dmitri Mendeleev's major contribution to the

field of chemistry?

Linhan Y.

Numerade Educator

Problem 69

Is it possible to distinguish between an element and a

compound? Explain.

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Problem 70

How are the properties of a compound related to those

of the elements that comprise it?

Linhan Y.

Numerade Educator

Problem 71

Which law states that a compound always contains the

same elements in the same proportion by mass?

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Problem 72

\begin{equation}

\begin{array}{l}{\text { a. What is the percent by mass of carbon in } 44 \text { of }} \\ {\text { carbon dioxide }\left(\mathrm{CO}_{2}\right) ?} \\ {\text { b. What is the percent by mass of oxygen in } 44 \mathrm{g} \text { of }} \\ {\text { carbon dioxide }\left(\mathrm{CO}_{2}\right) ?}\end{array}

\end{equation}

Linhan Y.

Numerade Educator

Problem 73

Complete Table 3.7 by classifying the compounds as

$1 : 1$ or $2 : 2,1 : 2$ or $2 : 1,$ and $1 : 3$ or $3 : 1 .$

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Problem 74

A $25.3-\mathrm{g}$ sample of an unknown compound contains

0.8 $\mathrm{g}$ of oxygen. What is the percent by mass of oxygen

in the compound?

Linhan Y.

Numerade Educator

Problem 75

Magnesium combines with oxygen to form magnesium

oxide. If 10.57 g of magnesium reacts completely with

6.96 g of oxygen, what is the percent by mass of oxygen

in magnesium oxide?

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Problem 76

When mercury oxide is heated, it decomposes into

mercury and oxygen. If 28.4 g of mercury oxide decom-

poses, producing 2.0 $\mathrm{g}$ of oxygen, what is the percent by

mass of mercury in mercury oxide?

Linhan Y.

Numerade Educator

Problem 77

Carbon reacts with oxygen to form two different compounds. Compound I contains 4.82 g of carbon for

every 6.44 g of oxygen. Compound II contains 20.13 $\mathrm{g}$

of carbon for every 53.7 $\mathrm{g}$ of oxygen. What is the ratio of

carbon to a fixed mass of oxygen for the two compounds?

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Problem 78

A 100 -g sample of an unknown salt contains 64 g of

chlorine. What is the percent by mass of chlorine in the

compound?

Linhan Y.

Numerade Educator

Problem 79

Which law would you use to compare $\mathrm{CO}$ and $\mathrm{CO}_{2}$ ?

Explain. Without doing any calculations, determine

which of the two compounds has the highest percent

by mass of oxygen in the compound.

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Problem 81

Which state(s) of matter are compressible? Which

state(s) of matter are not compressible? Explain.

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Problem 82

Classify each mixture as homogeneous or heterogeneous.

\begin{equation}

\begin{array}{l}{\text { a. brass (an alloy of zinc and copper) }} \\ {\text { b. a salad }} \\ {\text { c. blood }} \\ {\text { d. powdered drink mix dissolved in water }}\end{array}

\end{equation}

Linhan Y.

Numerade Educator

Problem 83

Phosphorus combines with hydrogen to form phosphine. In this reaction, 123.9 g of phosphorus combines with excess hydrogen to produce 129.9 g of phosphine.

After the reaction, 310 gof hydrogen remains unreacted.

What mass of hydrogen is used in the reaction? What

was the initial mass of hydrogen before the reaction?

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Problem 84

If you have 100 particles of hydrogen and 100 particles

of oxygen, how many units of water can you form? Will

you use all the particles of both elements? If not, what

will remain?

Linhan Y.

Numerade Educator

Problem 85

Classify each substance as a pure substance, a homogeneous mixture, or a heterogeneous mixture.

\begin{equation}

\begin{array}{llll}{\text { a. air }} & {\text { c. soil }} & {\text { e. sediment }} \\ {\text { b. aerosol }} & {\text { d. water }} & {\text { f. muddy water }}\end{array}

\end{equation}

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Problem 86

Identify each as a homogenous mixture, a heterogeneous mixture, a compound, or an element.

\begin{equation}

\begin{array}{l}{\text { a. pure drinking water }} \\ {\text { b. salty water }} \\ {\text { c. helium }}\end{array}

\end{equation}

\begin{equation}

\begin{array}{l}{\text { d. seawater }} \\ {\text { e. air }}\end{array}

\end{equation}

Linhan Y.

Numerade Educator

Problem 87

Cooking List physical properties of eggs before and

after they are cooked. Based on your observations, does

a physical change or chemical change occur when eggs

are cooked? Justify your answer.

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Problem 88

Ice Cream You might have noticed that while eating ice

cream on a hot day, some of the ice cream begins to

melt. Is the observed change in the state of the ice cream

a physical or a chemical change? Justify your answer.

Linhan Y.

Numerade Educator

Problem 89

Iced Tea Is a mixture of tea and ice homogeneous or

heterogeneous? Does that change as the ice melts?

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Problem 90

Sodium reacts chemically with chlorine to form sodium

chloride. Is sodium chloride a mixture or a compound?

Linhan Y.

Numerade Educator

Problem 91

Is air a solution or a heterogeneous mixture? What technique can be used to separate air into its components?

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Problem 92

Indicate whether combining the following elements yields a compound or a mixture,

\begin{equation}

\begin{array}{l}{\text { a. } \mathrm{H}_{2}(\mathrm{g})+\mathrm{O}_{2}(\mathrm{g}) \rightarrow \text { water }} \\ {\text { b. } \mathrm{N}_{2}(\mathrm{g})+\mathrm{O}_{2}(\mathrm{g}) \rightarrow \text { air }}\end{array}

\end{equation}

Linhan Y.

Numerade Educator

Problem 93

Interpret Data A compound contains the elements $X$

and $Y .$ Four samples with different masses were analyzed, and the masses of $X$ and $Y$ in each sample were plotted on a graph shown in Figure $3.24 .$ The samples

were labeled I, II, III, and IV.

\begin{equation}

\begin{array}{l}{\text { a. Which samples are from the same compound? How }} \\ {\text { do you know? }} \\ {\text { b. What is the approximate ratio of the mass of } X \text { to the }} \\ {\text { mass of } Y \text { in the samples that are from the same }} \\ {\text { compound? }}\end{array}

\end{equation}

\begin{equation}

\begin{array}{l}{\text { c. What is the approximate ratio of the mass of } X \text { to the }} \\ {\text { mass of } Y \text { in the sample(s) that are not from the same }} \\ {\text { compound? }}\end{array}

\end{equation}

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Problem 94

Apply Air is a mixture of many gases, primarily nitrogen, oxygen, and argon. Could distillation be used to

separate air into its component gases? Explain.

Linhan Y.

Numerade Educator

Problem 95

Analyze Is gas escaping from an opened soft drink an

example of a chemical or a physical change? Explain.

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Problem 96

Apply Give examples of heterogeneous mixtures for the

systems listed in Table $3.9 .$

Linhan Y.

Numerade Educator

Problem 97

Identify Lead Compounds A sample of a certain lead

compound contains 6.46 g of lead for each gram of oxy-

gen. A second sample has a mass of 68.54 $\mathrm{g}$ and contains

28.76 $\mathrm{g}$ of oxygen. Are the two samples the same?

Explain.

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Problem 100

Express the following numbers in scientific notation. (Chapter 2$)$

\begin{equation}

\begin{array}{ll}{\text { a. } 34,500} & {\text { d. } 789} \\ {\text { b. } 2665} & {\text { e. } 75,600} \\ {\text { c. } 0.9640} & {\text { f. } 0.002189}\end{array}

\end{equation}

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Problem 101

Perform the following operations. (Chapter 2$)$

\begin{equation}

\begin{array}{l}{\text { a. } 10^{7} \times 10^{3}} \\ {\text { b. }\left(1.4 \times 10^{-3}\right) \times\left(5.1 . \times 10^{-5}\right)} \\ {\text { c. }\left(2 \times 10^{-3}\right) \times\left(4 \times 10^{5}\right)}\end{array}

\end{equation}

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Problem 103

Graph the data in Table 3.10. What is the slope of the

line? (Chapter 2$)$

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Problem 104

Synthetic Elements Select a synthetic element, and

prepare a short written report on its development. Be

sure to discuss recent discoveries, list major research

centers that conduct this type of research, and

describe the properties of the synthesized element.

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Problem 105

\begin{equation}

\begin{array}{l}{\text { a. Compare the mass percent of carbon in charcoal, }} \\ {\text { indigo, and verdigris. }} \\ {\text { b. Compare the mass percent of oxygen in iron oxide }} \\ {\text { and Egyptian blue. }}\end{array}

\end{equation}

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Problem 106

List an example of an element and a compound from

Table 3.11 .

Linhan Y.

Numerade Educator

Problem 107

Is the production of charcoal from the dry distillation

of wood a chemical or a physical change? Explain.

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