measurement and significant figures€¦ · web viewa.11 supplement: predicting properties. given...
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Name: _________________________________________________ Textbook Notes Unit 2 and small part of Unit 1 Term 1
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 (C) or a physical property (P).
1. Gallium, used primarily in semiconductors and light emitting diodes (LEDs), is a soft, silver-colored metal.
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2. Helium is used to fill blimps because its density is lower than that of air, thus enabling these crafts to float.
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3. Zinc metal burns in air to form zinc oxide.
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4. Sodium metal must be stored under kerosene or nitrogen because of its high reactivity with oxygen and water.
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5. Bromine is a reddish-brown element, is the only nonmetallic element that exists in the liquid state at room temperature.
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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.
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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
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9. The compound boron nitride is almost as hard as diamond and is used for glass and diamond shaping and cutting.
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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:______________________________________________________________________________
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In general, how many chemical elements are known? __________________________________
Similarities and differences in the properties of elements are used to do what to the elements?
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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.___________________________________ ____________________________________
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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.
___________________________________ ____________________________________
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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?
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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?
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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?
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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: _________________________________________________
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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.
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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: choose either: alkali metals, halogens, or noble gas
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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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Second Half of First Quarter MaterialB.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 _______________________________
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iii. Cu ____________________________ vii. Na _______________________________
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.
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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:_______ _____________
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O: _______ O:_______ _____________B.8 pg. 37-38
List two every day examples that show the electrical nature of matter:
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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? ________________________________________________________________
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What makes an ionic compound neutral? ____________________________________________
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Explain how anions and cations are different. In your description, be sure to clearly explain what makes each different from the other.
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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. If not balanced, try to fix it
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) __________________________________________________________________________
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(c) C: _______ C: _______H:_______ H:_______O: _______ O:_______ (d) balanced? _________________________
2. HBr + Mg H2 + MgBr2
(a) __________________________________________________________________________
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(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) __________________________________________________________________________
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(c) C: _______ C: _______H:_______ H:_______O: _______ O:_______ (d) balanced? _________________________
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5. 2C3H5(NO3)3 3N2 + O2 +6CO2 + 5H2O
(a) __________________________________________________________________________
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(c) C: _______ C: _______H:_______ H:_______O: _______ O:_______ (d) balanced? _________________________
C.3 pgs. 157-159 All chemical changes can be interpreted as what? ______________________
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What happens when the subscript in a chemical formula is changed? ______________________
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What part of the chemical equation is adjusted to balance the equation? ____________________
Write the three suggestions to help you correctly balance equations:
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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–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.
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. 29
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 2.0 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 ?
7. How many grams equal 36.5 mol of Cu3(CO3)2(OH)2?Using Avogadro’s Number
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Avogadro’s number is 6.022 x 1023 Try putting that into your calculator. 1) Press 6.022
2) Press the 2nd button 3) Press the ,button. E should appear in the screen4) Type the exponent 23. This should be in the screen 6.022E23
1. sodium sulfate a) cation: __________ anion:___________ formula: ______________
b) molar mass: ______________ show work in space below
c) How many grams is equal to 2.71 moles of sodium sulfate? _______________________show work in space below
d) How many molecules are equal to 2.71 moles of sodium sulfate? ____________________show work in space below
2. osmium bromide a) cation: __________ anion:___________ formula: ___________
b) molar mass: ______________ show work in space below
c) How many moles are equal to 55.00 g of osmium bromide? _______________________show work in space below
d) Use your answer in c) to figure out how many molecules _____________________________are equal this many moles of osmium bromide. show work in space below
3. technetium selenide a) cation: __________ anion:________ formula: _____________
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b) molar mass: ______________ show work in space below
c) How many moles are equal to2.22x 1023 molecules _______________________technetium selenide ? show work in space below
d) Use your answer in c) to figure out how many grams ______________________________are equal this many moles of technetium selenide . show work in space below
4. chromium(II) phosphate a) cation: ________ anion:_________ formula: _____________
b) molar mass: ______________ show work in space below
c) How many moles are equal to 8.04x 1024 molecules _______________________chromium(II) phosphate? show work in space below
d) Use your answer in c) to figure out how many grams ______________________________are equal this many moles of chromium(II) phosphate. show work in space below
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Intro to Conversions
To make a peanut butter and jelly sandwich it takes 2 tablespoons of peanut butter and 0.5 tablespoon of jelly. As a formula:
If you have 8 tablespoons of peanut butter and an unlimited amount of jelly, how many sandwiches can you make?
If you have 20 tablespoons of jelly and an unlimited amount of peanut butter, how many sandwiches can you make?
For the junior class picnic, 115 peanut butter sandwiches are required. How many tablespoons of peanut butter were used to make these sandwiches?
How man tablespoons of jelly were used?
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Stoichiometry Practice [accompanies C7]Like the peanut butter sandwich example, coefficients can be used to convert between reactants and products. In chemistry, this is called stoichiometry
What is the maximum amount of moles of HNO3 that could be produced from the reaction of 4 moles of N2O5
a) balance the equation
N2O5 + H2O HNO3
b) find the given number and the chemical formula it goes with in the question above and write it in the first space. given in question coefficient and formula of unknown
matching coefficient and formula of given
c) look at the balanced equation. Write the coefficient (big number) and chemical formula of the one that matches the given across from the given. The diagonal chemical formulas must match.
d) read the question again and write the formula of what is unknown (asked for) on the line on top
e) multiply across the top and then divide by the bottom.
f) you now have the answer in moles. Write it in on the blank:___________________________
Part 2: How many grams of HNO3 is this equal to?
a) have moles want grams: need Molar Mass. Use the periodic table to get the molar mass of HNO3
Write it on the line. The molar mass is how many grams of the compound are equal to one mole.
g1 mole
b) take the amount of moles in (f) above (given) and write it in the first space. Make sure to write the word moles next to the number
given in question grams from molar mass
moles from molar mass.
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c) use the molar mass in the next spot, putting moles diagonal from moles and grams on top. Make sure to write the words next to the numbers.
d) multiply across tops and divide by bottom. Now you have grams! _____________________
Part 3: How many molecules of HNO3 is this equal to?
a) Whenever they want molecules (or atoms) Avogadro’s number is involved. BUT it can only be used with moles. Write it on the line below:
molecules or atoms1 mole
b) Take the amount of moles in (f) in Part 1 (given) and write it in the first space. Make sure to write the word moles next to the number
given in question Avogadro’s number of molecules
moles from Avogadro’s number.c) use Avogadro’s number in the next spot putting moles diagonal from moles and the big number on top. Make sure to write the words next to the numbers.
d) multiply across tops and divide by bottom. Now you have molecules ________________________
2) How many moles of oxygen will be produced from 3.98 moles of mercury oxide [HgO]?
a) Balance
HgO Hg + O2
b) convert moles of given to moles of unknown
____________________________
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How many grams of O2 is this equal to?a) Use periodic table to get molar mass of O2
g1 mole
b) convert moles of oxygen to grams of oxygen
____________________________
How many molecules of O2 is this equal to?a) Go back and find moles of oxygen to start with. Then use Avogadro’s number to convert moles to molecules
__________________________________
3) If 0.5 moles of AlCl3are produced from the following reaction, how many moles of CuCl2 did you start with?
a) balance
Al + CuCl2 AlCl3 + Cu
b) convert moles of given to moles of unknown
_______________________________
How many grams of CuCl2 does this equal?
a) use periodic table to get molar mass of CuCl2
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b) start with moles of CuCl2 and convert to grams using molar mass
_______________________________How many molecules of CuCl2 does this equal?a) Go back and find moles of CuCl2 to start with. Then use Avogadro’s number to convert moles to molecules
________________________________
Homework1) balance: Cl2 + Fe FeCl3
a) How many moles of FeCl3 could be made from 0.35 moles of chlorine?
b) How many grams of FeCl3 is this equal to? [need molar mass]
c) How many molecules of FeCl3 is this equal to?
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2) balance: KClO3 KCl + O2
a) How many moles of KClO3 is heated to produce 2.02 moles of oxygen gas?
b) How many grams of KClO3 is this equal to?
c) How many molecules of KClO3 is this equal to?
3. balance: C2H5OH + O2 CO2 + H2O
a) If 13 moles of oxygen was used, how many moles of carbon dioxide (CO2) is produced?
b) How many grams of CO2 is this equal to?
c) How many molecules of CO2 is this equal to?
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Study Guide Test Sections B6-B10
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).
_________________________________________________________________________________
3. Differentiate between protons and electrons in terms of their relative charges.
___________________________________________________________________________
___________________________________________________________________________
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+ ___________
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Study Guide Test Section C1. How does a balanced chemical equation demonstrate the law of conservation of matter?
_________________________________________________________________________________
_________________________________________________________________________________
_________________________________________________________________________________
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 + ____H2O40
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?
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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
1) Using the following balanced equation:
2 NaOH (aq) + H2SO4 (aq) 2 H2O (l) + Na2SO4 (aq)
a) How many moles of Na2SO4will be formed if you start with 12 moles of NaOH
b) How many molecules of Na2SO4 is amount of moles equal to?
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c) The molar mass of Na2SO4 is 142.04 gram/mol. How many grams of Na2SO4 is this amount of moles (solved for in part (a) equal to?
2) Using the following balance equation:
Pb(NO3)4 (aq) + 2 Li2SO4 (aq) Pb(SO4)2 (s) + 4 LiNO3 (aq)
a) How many moles of Pb(NO3)4 will be needed to produce 1.75 moles of LiNO3?
b) How many molecules of Pb(NO3)4 is amount of moles equal to?
c) How many grams of Pb(NO3)4 is this amount (found in part (a)) of moles equal to? [molar mass of 331.20 g/mol]
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