Name: _________________________________________________ Textbook Notes Unit 2 and small part of Unit 1 Term 1 2018

Materials: Structure and UsesUNIT 2 A.1 pg. 110-111A physical property is __________________________________________________________

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List examples of physical properties: 1. _____________________________

2.____________________________________ 3._________________________________

A physical change is __________________________________________________________

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List examples of physical changes: 1. _____________________________

2.____________________________________ 3._________________________________

A chemical change is __________________________________________________________

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Chemical properties are _________________________________________________________

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In your own words, explain chemical change and chemical properties in terms of how they relate to rusting of a metal.

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A.1 Supplement: Physical and Chemical Properties

Physical properties are properties that can be determined without altering the chemical makeup of a substance. Chemical properties relate to the types of chemical changes that a substance undergoes (or doesn’t undergo).

Using the space provided, classify each of the following statements as describing either a chemical property or a physical property.

1. Gallium, used primarily in semiconductors and light emitting diodes (LEDs), is a soft, silver-colored metal.

___________________

2. Helium is used to fill blimps because its density is lower than that of air, thus enabling these crafts to float.

___________________

3. Zinc metal burns in air to form zinc oxide.

___________________

4. Sodium metal must be stored under kerosene or nitrogen because of its high reactivity with oxygen and water.

___________________

5. Bromine is a reddish-brown element, is the only nonmetallic element that exists in the liquid state at room temperature.

___________________

6. Isopropyl alcohol (also known as rubbing alcohol) readily evaporates when it is placed on your skin.___________________

7. Carbon dioxide and water are produced when gasoline undergoes combustion in a car engine.

___________________

8. More energy is needed to raise the temperature of 1 g of water than is needed to raise the temperature of 1 g of any metal

___________________

9. The compound boron nitride is almost as hard as diamond and is used for glass and diamond shaping and cutting.

___________________

10. Hydrogen sulfide is removed from the natural gas used to heat homes through a reaction with oxygen.

___________________

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A.2 Read Developing Skills Physical and Chemical Properties pg. 111-112

Write the answers to questions 1-9 by classifying each as a physical or chemical property.

1. Pure metals have a high luster ____________________________

2. The surfaces of some metals become dull when exposed ____________________________ to air.

3. Nitrogen gas, which is a relatively nonreactive element ____________________________ at room temperature, can form nitrogen oxides at the high temperatures of an operation automobile engine.

4. Milk turns sour if left too long at room temperature. ____________________________

5. Diamonds are hard enough to be used as a coating for ____________________________ drill bits.

6. Metals are typically ductile. ____________________________

7. Leavened bread dough increases in volume if it is ____________________________ allowed to rise before baking.

8. Unreactive argon gas, rather than air, is used to fill ____________________________ many light bulbs to prevent the metal filament wire inside the bulb from being destroyed through oxidation.

9. Generally, metals are better conductors of heat and ____________________________ and electricity than are nonmetals.

A. 4 pg. 114All matter is composed of ______________________________________. Explain why one element differs from another:______________________________________________________________________________

______________________________________________________________________________

In general, how many chemical elements are known? __________________________________

Similarities and differences in the properties of elements are used to do what to the elements?

______________________________________________________________________________

What are the two major classes of elements? ________________________________

________________________________

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Some examples of metals include iron (Fe), tin (Sn), aluminum (Al), and copper (Cu). Based on your previous knowledge of these metals, give some physical properties of metals. Include state of matter.___________________________________ ____________________________________

____________________________________ ____________________________________

Some examples of nonmetals include carbon (C), oxygen (O), and sulfur (S). Based on your previous knowledge of these non-metals, give some physical properties of non-metals. Include state(s) of matter.

___________________________________ ____________________________________

____________________________________ ____________________________________

Explain what you would expect from an element that is a metalloid.

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A. 6 pg. 117-119

What is the periodic table used for?

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Who is credited with publishing the periodic table in use today?

____________________________________

Why is the periodic table in use today similar to moon-phase calendar? (see Fig. 2.9)

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Describe the two characteristics of elements used in the 1800s to organize periodic tables.

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A. 8 pg. 120-121

What do we now expect of all elements found in the leftmost column of the periodic table?

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What about the ones in the rightmost column?_________________________________________

Name the three smaller particles that compose atoms. Write the charge above the name. Fig. 2.11

________________________ _______________________ ___________________________

What does the atomic number identify? _____________________________________________

What does atomic number have to do with the way the modern periodic table is organized?

______________________________________________________________________________

If an atom is electrically neutral, it must have equal parts of which two particles written above?

________________________ _______________________

Look at the periodic table in the back cover of your book:If the number of protons in an atom is 10, what element is it? ________________________

If the atomic number is 20, what element is it? ________________________

Which two particles written above are found in the nucleus?

________________________ _______________________

Which two particles written above are combined to make the mass number?

________________________ _______________________

Therefore the mass number is the mass of the nucleus!!

Why doesn’t the mass of the electron contribute to the mass of the atom?

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What is an isotope? ____________________________________________________________

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A.8 Supplement: The Pattern of Atomic Numbers

Using a periodic table, fill in the chart with the correct information. Assume that all atoms are electrically neutral.

Name Symbol Atomic Number

Mass Number

# of Protons

# of Neutrons

# of Electrons

1. boron B 5 11 5 6 52. zinc 31

3. K 42

4. 22 27

5. 122 51

6. U 146

7. 47 60

8. fermium 257

9. cesium 79 55

10. 42 97

11. 120 78

12. krypton 47

13. 86 222

14. N 15

15. 7 7

16. What similarities exist between the answers to questions 14 and 15 on the table?

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17. What differences exist between the answers to questions 14 and 15 on the table?

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18. What term can be applied to atoms like those described in questions 14 and 15 on the table?

___________________________________________

19. What is the difference between mass number (used in this exercise) and atomic mass (found on the periodic table)?_____________________________________________________________________________________

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A. 10 pg. 125

Explain the difference on the periodic table between periods and groups.

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What is the name for most of the elements found in the leftmost column of the periodic table?

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Which element in this column is not part of this group? ________________________________

What about the ones in the rightmost column?_________________________________________

What about the column to the left of the one named above? ______________________________

Find fluorine (atomic number 9) on the periodic table. If you know some of the properties of fluorine, what can be said about the properties of chlorine (atomic number 17)?

______________________________________________________________________________

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A. 11 Answer the questions to Predicting Properties on pg. 126

1. Estimate the boiling point of krypton. __________________

Explain how you got your answer: _________________________________________________

______________________________________________________________________________

2. (a) Estimate the melting point of rubidium. __________________ (b) Do you expect the melting point of sodium to be higher or lower

than rubidium? __________________On what evidence did you base your answer? (Write answer in space below)

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A.11 Supplement: Predicting Properties

1. Given that the density of helium (He) is 0.1785 g/cm3 and the density of argon (Ar) is 1.784 g/cm3, estimate the density of neon.

2. Would you expect the density of krypton (Kr) to be higher or lower than that of argon (Ar)? Explain your answer.

_________________________________________________________________________________

_________________________________________________________________________________

3. Given that the boiling point of nickel (Ni) is 3003 K and the boiling point of platinum (Pt) is 3560 K, estimate the boiling point of palladium (Pd).

4. Are the chemical properties of sodium more likely to be similar to potassium or magnesium? Explain.

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5. Discovery of element 113 has not yet been proven or verified. Assuming its discovery is accepted some day, what would you expect the approximate atomic mass to be? Explain. (Answer in space below)

An alphabetical chart of the elements is found on pgs 129-130.

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UNIT 1 B.3 pg. 28-30 Start on section Mixtures and Solutions

How can the components of a mixture be separated? ___________________________________

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Describe a heterogeneous mixture. Explain how you know it is heterogeneous.

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Describe a suspension. Explain how you know it is a suspension.

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Describe a colloid. Explain how you know it is a colloid.

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Describe a homogenous mixture. Explain how you know it is homogeneous.

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In a salt water solution, what part is the solute? ________________________

what part is the solvent? ________________________Use figure 1.24 to help classify the following types of matter as Element, Compound, Solution, Colloid, SusPensionunopened soda (water, sugar, CO2, etc.) ____________________

water (H2O) ____________________

bromine (Br) ____________________

orange juice (water, citric acid and organic matter) ____________________

milk (water, fats, organic materials) ____________________

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B.4 pg. 31Why are atoms known as the building blocks of matter?

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Give an example of each and explain the difference between an element and a compound.

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What are two reasons why elements and compounds are considered substances?

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What holds the atoms of a molecule together? ________________________________________

Study Guide Test Section A

1. Identify each chemical and physical property of calcium that is described in the following paragraph.

a) Calcium is a shiny, silvery-white metal. When it is exposed to moist air, it readily tarnishes. At room temperature, calcium exists in the solid state and its melting point is 842 °C. It reacts with acid and with water to yield hydrogen gas.

Chemical Properties:

1) ______________________________________________________________________________

2) _______________________________________________________________________________

Physical Properties:

1) ____________________________________ 2)__________________________________

3) _____________________________________ 4)________________________________________ b) After reading the above information, imagine a student wrote the following observations after doing a lab where he had to identify a piece of silver metal that is possibly calcium. Circle the errors in the student’s lab observations. Under the paragraph, explain what the student did wrong.

[This font is the student’s handwriting]

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I believe that this metal is calcium. It has the physical properties of being silver and a metal solid. It has the chemical properties of being shiny because it is chemically reacting with light to be shiny. I tested its melting point and found that it melted at 842 0C. This is a chemical property of melting when it gets very hot (842 0C) because it is chemically reacting with heat to melt. I also tested it by dropping it in some acid. I saw bubbles which showed a gas was present. This is a chemical property because it is reacting with acid.

Explain what the student did wrong:

2. Analyze the following data and classify each substance as a metal, nonmetal, or metalloid.

Element Malleable or Brittle/Color?

Shiny or Dull? Conductor? Reacts with

Acid?Metal, Nonmetal, or

Metalloid?

A brittle/yellow dull yes no

B malleable/silver shiny yes yes

C brittle/grey dull no no

D brittle/black dull yes no

E malleable/grey shiny yes yes

3. The melting point of fluorine is –219 C while that of bromine is –7.3 C. Estimate the melting point of chlorine. Explain how you arrived at your estimation.

4. Name the family to which each element belongs:

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a. K ________________________________ Ne _________________________________

b. Kr________________________________ I___________________________________

5. Complete the following table:

Element Symbol Atomic Number

Number of Protons

Number of Neutrons

Mass Number

Neon 20

6 8

7 14

Na 23

6. Identify the element that is described by each of the following statements:a. This element is in the alkali metals group

and in the same period as the metals used in a penny._______________________________

b. This element is a halogen. It is in the same period as the element that is the gas which is used by your body and necessary for your life._______________________________

c. This element is a noble gas. It is in the same period as the liquid metal that used to be used in thermometers. __________________________________________

Section B.3-B.4 Study GuideComplete each of the following questions.

1. Carbon tetrachloride, CCl4 is a liquid that can be used in dry cleaning. When 5.0 g of bromine is added to 75 g of clear colorless CCl4, the mixture has a reddish-brown color. Over time, no settling out is observed. When the mixture is filtered, no residue is observed on the filter paper. When a light beam is directed at the mixture, its path through the mixture is not visible. Is the mixture a solution, colloid or suspension? Explain your answer by giving the definitions of solution, colloid, and suspension.

___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________

__________________________________________________________________________________

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2. Classify each of the following as an element or a compound.

a. NaCl ___________________________ b. C ___________________________________

c. Hg ___________________________ d. KNO3 _______________________________

3. Explain the difference between solute and solvent using salt water as your example. Be sure to give the definitions of solute and solvent in your answer.

4. Explain the difference between a homogeneous mixture and a heterogeneous mixture using Coke and Chex Mix as your examples. Be sure to give the definitions of the types of mixtures in your answer.

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B.6 Answer these questions after reading the material on pg. 34-35 The chemical formulas of common compounds are listed below. Explain how many of each element is found in the compound.

table salt NaCl (sodium chloride) ___________ sodium ___________ chlorine

baking soda NaHCO3 (sodium bicarbonate) ____ sodium ____ hydrogen ____ carbon ____ oxygen

chalk CaCO3 (calcium carbonate) _______ calcium ________ carbon _______ oxygen

table sugar (sucrose) C12H22O11 ________ carbon________ hydrogen _______ oxygen

octane (found in gasoline) C8H18 ________ carbon________ hydrogen

Label the reactants and the products for the reaction of the combustion of gasoline in your car:

2C8H18(l) + 25O2(g) 16CO2(g) + 18H2O (l)

count how many atoms on each side: Like math, distribute the number in front of the formula.

___C ___H ___O ___C ___H ___O Do the amounts match? ___________

Copy the information from Table 1.3

ELEMENTS THAT EXIST AS DIATOMIC MOLEULESElement Formula Element Formula

B.7 Use the periodic table or the table of elements to answer the questions 1. Name the element represented by each of these symbols:

i. P ____________________________ v. Br _______________________________

ii. Ni ____________________________ vi. K _______________________________

iii. Cu ____________________________ vii. Na _______________________________

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b. Which elements in question 1 have symbols that correspond to their English names?

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c. Which is more likely to be the same throughout the world, an element’s symbol or its name? Explain.

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2. Name the elements and give the number of atoms of each element:Element Names Amount of each Element

H2O2 H:

O

H:

O:CaCl2 Ca:

Cl:

Ca:

Cl:H2SO4 H:

S:

O:

H:

S:

O:

3. CH4(l) + 2O2(g) CO2(g) + 2H2O (l) a. Write a sentence describing the equation in terms of molecules. Use the words reactant and products and the specific names that the formulas stand for.

______________________________________________________________________________

______________________________________________________________________________

b. Identify the molecules as either an element or a compound. You can do this above the formulas.

c. Count the number of each element on each side of the reaction. (atom inventory) Remember, the big numbers (coefficients) are distributed to each element in the formula.

do they match? yes or noC: _______ C: _______ _____________H:_______ H:_______ _____________O: _______ O:_______ _____________

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B.8 pg. 37-38

List two every day examples that show the electrical nature of matter:

______________________________________________________________________________

______________________________________________________________________________

Summarize the electrical properties of matter using words and an illustration: [ fig at top of pg 38]

Name the parts of an atom and state their charges:

part charge

B.9 pg. 38-41

What is an ion? ________________________________________________________________

______________________________________________________________________________

What makes an ionic compound neutral? ____________________________________________

_____________________________________________________________________________

Explain how anions and cations are different. In your description, be sure to clearly explain what makes each different from the other.

______________________________________________________________________________

______________________________________________________________________________

What is a polyatomic ion? _______________________________________________________

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B.10 pg. 41Fill in the table after reading the descriptions of the compounds in statements 1-6

Cation Anion Formula Name1.

2.

3.

4.

5.

6.

B.9 & B.10 Supplement: Ions and Ionic Compounds

Complete the data table identifying the composition of each ionic compound. Names and formulas of polyatomic ions can be found in Table 1.4 of your textbook.

Remember these rules as you write formulas for ionic compounds: Write the cation first, and then write the anion. The correct formula will contain the fewest positive and negative ions needed to make the total electrical

charge zero.As you write the names of ionic compounds, remember to: Write the name of the cation first, and then write the anion name. Some metal atoms form ions with different charges under different conditions. To specify the charge for these

ions, Roman numerals are used in parentheses after the name of the metal. These include: copper, lead, iron, mercury.

Anions composed of a single atom have the last few letters of the element’s name changed to the suffix –ide.

Example: (a) Table salt is NaCl. It is called sodium chloride, not chlorine, because the anion changes its name slightly when it makes a bond. The first atom is the cation (sodium [Na+]),the second atom is the anion (chlorine, now called chloride, [Cl-]).

(b) Chalk is calcium carbonate CaCO3. Notice there are three capital letters and it ends in -ate , not -ide. This is the clue that a polyatomic ion is present. Carbonate is the anion [CO3

2-]. Calcium is the cation [Ca2+].

Use the periodic table of ions to help. It is found on the back of the periodic table at the end of this packet. There is a special box that lists the polyatomic ions.

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Cation Anion Formula Name1. calcium oxide

2. BaCl2

3. H NO3-

4. KBr

5. iron(III) sulfate

6. K+ SO32-

7. Na3PO4

8. silver sulfide

9. Zn2+ Br-

10. barium fluoride

11. Al3+ PO43-

12. K2S

13. magnesium oxide

14. Ba2+ SO42-

15. zinc phosphate

17. ScCl3

19. Pb2+ Br-

20. LiNO3

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UNIT 2 C.1 pg. 153

Explain the law of conservation of matter in your own words:

______________________________________________________________________________

______________________________________________________________________________

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C.1 Supplement: Keeping Track of Atoms1. A chemical equation is balanced if there are ___________________________ of each kind

of___________________________on both sides of the equation.

2. Accounting for atoms: determine the number of atoms of each kind in each of the following:

a. CaCO3 = ______ Ca ______ C ______ O

b. (NH4)2SO4 = ______ N ______ H ______ S ______ O

c. 3 H2 = ______ H

d. 4 Mg(OH)2 = ______ Mg ______ O ______ H

e. Ba(NO3)2 = ______ Ba ______ N ______ O

3. For each equation, list the number of each type of atom shown on the reactant side and the product side of the arrow. Also indicate whether the overall equation is balanced.

a. 2 Na + 2 H2O → 2 NaOH + H2

Reactants Products

_____________ Na _____________

_____________ H _____________

_____________ O ________________ Balanced? Yes ____ No____

b. 4 NH3 + 6 NO → 5 N2 + 6 H2OReactants Products

_____________ N _____________

_____________ H _____________

_____________ O ______________ Balanced? Yes ____ No____

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c. NaCl + F2 → NaF + Cl2

_____________ Na _____________

_____________ Cl _____________

_____________ F ______________ Balanced? Yes ____ No____

d. 3 NaBr + H3PO4 → 2 HBr + Na3PO4

_____________ Na _____________

_____________ Br _____________

_____________ H _____________

_____________ P _____________

_____________ O _____________ Balanced? Yes ____ No____

e.N2H4 + N2O4 → 3 N2 + 4 H2O Balanced? Yes ____ No____

f.4 Ag + 4 H2S + O2 → 2 Ag2S + 4 H2O Balanced? Yes ____ No____

g.2 Bi + 3 F2 → 2 BiF3 Balanced? Yes ____ No____

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h.Al + Ni(NO3)2 → Al(NO3)3 + Ni Balanced? Yes ____ No____

i.3 NaBH4 + 4 BF3 → 2 B2H6 + 3 NaBF4 Balanced?  Yes ____ No____

j.4 C3H5(NO3)3 → 6 N2 + O2 + 12 CO2 + 10 H2O Balanced? Yes ____ No____

k.Ca10F2(PO4)6 + 7 H2SO4 → 2 HF + 3 Ca(H2PO4)2 + 7 CaSO4

Balanced? Yes ____ No____

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C.2 Read Developing Skills Accounting for Atoms pg. 155-157Write the answers to questions1-5. For each question, (a) write an interpretation of the statement in words (b) omit (c) complete an atom inventor, (d) decide if it is balanced. There are answers to the sample question that can be used if you need help.

1. CH4 + 2O2 CO2 + 2H2O

(a) __________________________________________________________________________

______________________________________________________________________________

(c) C: _______ C: _______H:_______ H:_______O: _______ O:_______ (d) balanced? _________________________

2. HBr + Mg H2 + MgBr2

(a) __________________________________________________________________________

______________________________________________________________________________

(c) Br: _______ Br: _______H:_______ H:_______Mg: _______ Mg:_______ (d) balanced? _________________________

3. 4 Ag + 4 H2S + O2 2Ag2S + 4H2O

(a) __________________________________________________________________________

______________________________________________________________________________(c) Ag: _______ Ag: _______

H:_______ H:_______S: _______ S:_______O: _______ O:_______ (d) balanced? _________________________

4. C6H10O5 + 6O2 6CO2 + 5H2O

(a) __________________________________________________________________________

______________________________________________________________________________

(c) C: _______ C: _______H:_______ H:_______O: _______ O:_______ (d) balanced? _________________________

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5. 2C3H5(NO3)3 3N2 + O2 +6CO2 + 5H2O

(a) __________________________________________________________________________

______________________________________________________________________________

(c) C: _______ C: _______H:_______ H:_______O: _______ O:_______ (d) balanced? _________________________

C.3 pgs. 157-159 All chemical changes can be interpreted as what? ______________________

______________________________________________________________________________

What happens when the subscript in a chemical formula is changed? ______________________

______________________________________________________________________________

What part of the chemical equation is adjusted to balance the equation? ____________________

Write the three suggestions to help you correctly balance equations:

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

C.3 Supplement: Nature’s Conservation—Balanced Chemical Equations

Balance the following equations.

1. _____H2 + _____O2 → _____H2O

2. _____Mg + _____O2 → _____MgO

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3. _____Ca + _____H2O → _____Ca(OH)2 + _____H2

4. _____Cu + _____HgNO3  →_____Cu(NO3)2 + _____Hg

5. _____C3H8 + _____O2 → _____CO2 + _____H2O

6. _____Al + _____F2 →_____AlF3

7. _____Fe + _____O2 →_____Fe2O3

8. _____Fe3O4 + _____H2 →_____Fe + _____H2O

9. _____HBr +_____ O2 →_____Br2 + _____H2O

10. _____Al2O3 + _____HCl→_____AlCl3 + _____H2O

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11. _____NH4OH + _____FeCl3→ _____Fe(OH)3 + _____NH4Cl

12. _____NH3 + _____O2 →_____NO +_____ H2O

13. _____I2 + _____HNO3→_____HIO3 + _____NO2 + _____H2O

14. _____CaO + _____P2O5→_____Ca3(PO4)2

15. _____NaOH + _____Al2(SO3)3→_____Na2SO3 + _____Al(OH)3

C.4 159-161

Correctly balance the following equations. Perform an atom inventory at the end to make sure it is correct.1. a. C(s) + O2(g) 2CO(g)

b. Fe2O3(s) + CO(g) Fe(l) + 3 CO2(g)

2. CuO(s) + C(s) Cu(s) + CO2(g)

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3. O3(g) O2(g)

4. NH3(g) + O2(g) NO2(g) + H2O(l)

5. Cu(s) + AgNO3(aq) Cu(NO3)2(aq) + Ag(s)

6. C8H18(l) + O2(g) CO2(g) + H2O(g)

C.5 p. 161-163

What is the name and symbol for the chemist’s dozen? _________________________________

Write Avogodro’s number in scientific notation. ______________________________________

If you wrapped a paper clip chain around the earth that equaled a mole of paperclips, how many times would it go around the earth? ____________

How many grams does one mole of water equal? ____________

What value must be known in order to find themass of one mole of a substance? ____________________________________

Where can you find the numerical value of an element’s atomic weight? ____________________________________

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C.5 Supplement: Molar Masses

The molar mass of a substance is the mass of one mole (6.02 × 1023 units) of the substance. The mass in grams of one mole of an element’s atoms is equal to the numerical value of that element’s atomic weight. These values for each element can be found on the periodic table.

To find the molar mass of a substance, multiply the number of moles of each element by the molar mass of the element. Then add the masses of the various elements.

Example 1: What is the molar mass of iron(III) oxide, Fe2O3?2 mol Fe = 2 × 55.85 g = 111.7 g Fe3 mol O = 3 × 16.00 g = 48.00 g OMolar Mass of Fe2O3 = (111.7 g Fe + 48.00 g O) = 159.7 g Fe2O3

Example 2: What is the molar mass of magnesium hydroxide, Mg(OH)2?1 mol Mg = 1 × 24.31 g = 24.31 g Mg2 mol O = 2 × 16.00 g = 32.00 g O2 mol H = 2 × 1.008 g =  2.016 g HMolar Mass of Mg(OH)2 = (24.31 g + 32.00 g + 2.016 g) = 159.7 g Mg(OH)2

Determine the molar mass of each substance.

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1. fluorine gas: F2

2. copper (II) chloride: CuCl2

3. aluminum oxide: Al2O3

4. potassium hydroxide: KOH

5. sodium bicarbonate: NaHCO3

6. calcium phosphate: Ca3(PO4)2

7. ammonium sulfate: (NH4)2SO4

8. malachite: Cu2CO3(OH)2

9.alum: KAl(SO4)2• 12H2O

10. glucose: C6H12O

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C.6 pg. 163 Fill in the table with the chemical formula and the molar mass of each of the following substances:

name formula molar massnitrogen atoms

nitrogen molecules

sodium chloride (table salt)

sucrose (table sugar)

chalcopyrite (copper mineral)

magnesium phosphate

caffeine

calcium hydroxyapatite (a mineral found in teeth)

alunite (aluminum mineral)

C.7 Supplement: Molar Relationships-II

When the molar masses and molar relationships between reactants and products are known, chemists can calculate the amounts of material they need or will produce using a particular reaction.

1. On a small scale, calcium can be isolated through the reaction of calcium chloride with sodium metal, as shown in the following equation:

CaCl2 + 2Na → Ca + 2NaCl

a. How many moles of Na are needed to react with 7.00 mol CaCl2?

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b. How many moles of NaCl are produced by the reaction of 14.0 mol Na?

c. How many moles of Ca are produced from 3.5 mol Na?

2. Magnetite, an iron ore, can be reduced to form metallic iron by a process called pyrometallurgy. One reaction that occurs during this process is:

Fe3O4 + 4CO → 3Fe + 4CO2

a. How many moles of CO are needed to react with 3.5 mol Fe3O4?

b. How many moles of CO2 are produced by the reaction of 7.00? mol CO? Assume adequate amount of Fe3O4.

c. How many mol of Fe are produced from 5.0 mol CO? Assume adequate amount of Fe3O4.

C.7 Supplement: Molar Relationships–IMole-Mass ConversionsOnce the molar mass of a substance is known, it is fairly easy to calculate moles from grams or grams from moles.

Example 1: How many moles are present in 352 g of iron(III) oxide, Fe2O3?

Step 1: Calculate the molar mass of iron (III) oxide.

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By adding the mass of two moles of iron atoms and three moles of oxygen atoms, the molar mass is calculated to be 160.0 g.

This can be expressed in two ways as a conversion factor. It is either:a. 160.0 g of Fe2O3 contains 1 mole (160.0 g/1 mol) orb. 1 mole of Fe2O3 contains 160 g (1 mol/160.0 g)

Step 2: Arrange the molar mass so the original units cancel and the desired units are on top.

Example 2: How many grams are present in 1.43 moles of magnesium hydroxide, Mg(OH)2?

Step 1: Calculate the molar mass of magnesium hydroxide.

By adding the mass of one mole of magnesium atoms, two moles of oxygen atoms, and two moles of hydrogen atoms, the molar mass is calculated to be 58.312 g.

Step 2: Arrange the molar mass so the original units cancel and the desired units are on top.

Calculate the following.

1. How many grams equal 1.0 mol of Azurite, Cu3(CO3)2(OH)2,?

2. How many grams equal 6.3 mol of N2?

3. How many moles equal 84.6 g of NaCl?

4. How many moles equal 564 g of C12H22O11?

5. How many grams equal 3.95 mol of CuFeS2?

6. How many moles equal 0.985 g of Cu2CO3(OH)2 ?31

7. How many grams equal 36.5 mol of Cu3(CO3)2(OH)2?

C.9 pg. 166-168

How can you find the percent composition of a penny?

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Why does percent composition help geologists?

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What two factors must be taken into account when deciding on the quality of a particular ore?

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Percent Composition Developing Skills. Show your work when you perform calculations.

Write the formula for percent below:

Solve for percent abundance. Show your work in the box. 1) A 90 g sample of limestone is composed of three different elements.

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Element amount in sample

percent abundance(round to nearest whole number)element mass divided by sample mass X 100 = %

Calcium 73.7 g

Carbon 7.3 g

Oxygen 9.0 g

2) A 883 g sample of granite is composed of three different elements. Element amount

in sample

percent abundance

silicon 737.7 g

potassium 27.3 g

aluminum

Study Guide Test Sections B6-B10

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1. Complete the following table by naming the elements present and the number of each type of atom.

Compound Element Names Number of Atoms of Each Element

CO2

CaCl2

Al2S3

NH4NO3

2. Write a chemical equation that represents the following word equation:One molecule of nitrogen (N2) reacts with 3 molecules of hydrogen (H2) to form 2 molecules of ammonia (NH3).

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3. Differentiate between protons and electrons in terms of their relative charges.

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4. Decide whether each of the following atoms is electrically neutral. If it is not neutral, tell if it is a cation or anion.

Element Protons Electrons Neutral? Cation or Anion

Gold 79 76

Helium 2 2

Fluorine 9 10

5. Classify the following as anions, cations, or electrically neutral atoms.

a. K+ _____________ b. Ag _____________ c. N3- _____________ d. Ba2+ ___________

6. Write the symbol and show the electrical charge (if any) on the following atoms or ions:

a. helium with one proton and one electron _____________

b. lithium with three protons and two electrons _____________

c. fluorine with nine protons and ten electrons _____________

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Study Guide Test Section C1. How does a balanced chemical equation demonstrate the law of conservation of matter?

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2. For each of the following equations, complete an atom inventory and indicate whether the equation is balanced. If it is not balanced, balance it.

a. Rb + RbNO3 → Rb2O + N2

________ Rb________

________ N________

________ O________ Balanced?_____Yes_____No

b. HCl + NaOH → NaCl + H2O

________ H________

________ Cl________

________ Na_______

________ O________

________ H________ Balanced?_____Yes_____No

3. Balance each of these chemical expressions.

a. ____Al2O3 → ____Al + ____O2

b. ____Al + ____S8 → ____Al2S3

c. ____H 3PO4 + ____Mg(OH)2 → ____Mg3(PO4)2 + ____H2O

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4. Find the molar mass of each of the following substances: Show work!

a. F2 _____________________________ b. PbS ________________________________

c. MgSO4 _______________________________d. Al(OH)3________________________________

5. For the equation [show work]

2C2H6 + 7O2 → 4CO2 + 6H2O

a. How many moles O2 are needed to react with 10 mol C2H6?

b. How many moles CO2 are produced by the reaction of 9.0 mol O2?

c. How many moles H2O are produced from 3.5 mol C2H6?

6. Zinc minerals exist as smithsonite, ZnCO3, at Mining Site A and as sphalerite, ZnS, at Mining Site B. Solve for the percent composition of zinc in each mineral. Show workZnCO3 ZnS

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Based only on percent composition of the minerals, at which site would mining of zinc be most feasible?

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7. Fill in the chart. Use the periodic table of ions to help

cation anion formula name

a. KBr

b. iron(III) sulfate

c. K+ SO32-

d. Na3PO4

e. silver sulfide

8. The following balanced chemical equation below shows the burning of butane in oxygen. Please label the following parts that are found in the equation, using the letters given to abbreviate.

Subscripts (S) Coefficients (C) Reactants (R) Products (P)

2 C4H10 + 13 O2 8 CO2 + 10 H2

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