1. Chapter 8 Chemical Reactions

2. Chemical Equations
______________: uses _________ and ____________ to represent the identities and relative molecular or molar amounts of the __________ and _________ in a chemical rxn.
__________ + reactant → ________ + product
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3. Chemical Equations ___________ of a chemical rxn:
Evolution of ______ and _______.
Production of a ______.
Formation of a __________.
_________change.
____________: a ______ that is produced as a result of a chemical rxn in solution and that __________ from the solution
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4. Chemical Equations _________________ of a Chemical Equation:
The eq. must _____________ known __________.
The eq. must contain the _________________ for the ___________ and _________________.
The Law of __________________ must be satisfied.
____________: a small whole number that appears ___________ a formula in a chemical eq.
ex. 2H2O means either 2 _________________ or 2 _____________.
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5. Chemical Equations
________________: an eq. in which the reactants and products in a chemical rxn are represented by ________.
ex. Methane + oxygen → carbon dioxide + water
___________________: represents the reactants and products of a chemical rxn by their __________________.
Ex. CH4(g) + O2(g) → CO2(g) + H2O(g)
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6. Chemical Equations
___________________________: for mass to remain constant _____________________ a chemical rxn, the number of ______ of each element must be the same before and after a chemical rxn
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7. Chemical Equations Ex. Ca + O2 → CaO
2 oxygen atoms → only one oxygen atom
Ca + O2 → 2CaO the coefficient means calcium oxide molecules are produced.
Now the __________________ balance, but there are ___ Ca atoms in the products and only___ in the reactants.
2Ca + O2 → 2CaO
Now the equation is ___________with regard to the number of atoms.
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8. Chemical Equations Ex. Methane + oxygen → Carbon dioxide + water
CH4 + O2 → CO2 + H2O
C = C = 1
H = H = 2
O = O = 3
You need to ___________ the number of ___________ atoms in the __________.
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9. Chemical Equations Methane + oxygen → Carbon dioxide + water
CH4 + O2 → CO2 + 2H2O
C = C = 1
H = H = 4
O = O = 4
Now you need to _________ the number of ___________ atoms in the ___________.
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10. Methane + oxygen → Carbon dioxide + water
Chemical Equations
Methane + oxygen → Carbon dioxide + water
CH4 + 2O2 → CO2 + 2H2O
C = C = 1
H = H = 4
O = O = 4
___________!
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11. Practice
Write the reaction for ________________ reacting with copper to form ________________ and silver.
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12. Practice
Write the reaction for silver (I) nitrate reacting with copper to form copper (II) nitrate and silver.
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13. Significance of a Chemical Rxn
The __________ of a chem. rxn. indicate relative __________ of reactants and products.
The relative ___________ of reactants and products can be determined by the ___________.
The reverse rxn. has the same relative amounts as the forward rxn.
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14. Significance of a Chemical Rxn
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15. Practice Try writing balanced equations for the following reactions:
2) Aluminum reacts with oxygen to form aluminum (III) oxide.
3) Chlorine reacts with lithium bromide to produce lithium chloride and bromine.
4) Sodium phosphate reacts with iron (II) chloride to produce sodium chloride and iron (II) phosphate.
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16. Types of Chemical Rxns 1) ___________ Rxns: A + B → AB
AKA composition rxn, ____________ substances combine to form a new compound. (*__________________!)
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17. Types of Chemical Rxns 1) Sythesis Rxns:
Rxn of elements with ______________: products are __________ and ___________.
Rxn of ________ with __________: products are ______________
Rxns with oxides: metals form __________, nonmetals form ___________.
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18. 2) _____________ Reactions:
Types of Chemical Rxns
2) _____________ Reactions:
AB → A + B
A rxn in which a _________________ undergoes a reaction that produces into __________________. (* ____________)
Ex. 2H2O → 2H2 + O2
This rxn is carried out through ___________: the decomposition of a substance by an _______________.
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19. 3) ___________________ Reactions:
Types of Chemical Rxns
3) ___________________ Reactions:
A + Bx → Ax + B
One element ______________ a similar element in a compound. (*The reactants are always __________________________)
Ex. Mg + CuSO4 → MgSO4 + Cu
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20. 4) _________________ Reactions:
Types of Chemical Rxns
4) _________________ Reactions:
Ax + By → Ay + Bx
Ions of ____________________ exchange places in an aqueous solution to form two new compounds. (*______________________________ __________________.)
Ex. 2HCl + CaCO3 → H2CO3 + CaCl2
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21. 4) _____________________ Reactions:
Types of Chemical Rxns
4) _____________________ Reactions:
Formation of a ________________ (ppt).
Formation of a _________.
Formation of _____________.
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22. 5) ______________ Reactions:
Types of Chemical Rxns
5) ______________ Reactions:
A substance combines with ______________, releasing a large amount of energy in the form of light and heat.
A + O2 → CO2 + H2O
Typically…
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23. Practice What type of rxn are the following
a) CO2 + H2O → H2CO3______________________
b) Cl2 + 2KI → 2KCl + I2_____________________
c) CaCO3 → CaO + CO2_____________________
d) 2HCl + CaCO3 → H2CO3 + CaCl2____________
e) Fe + CuSO4 → FeSO4 + Cu_________________
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24. Practice 5) What type of rxn are the following
a) CO2 + H2O → H2CO3_____________________________
b) Cl2 + 2KI → 2KCl + I2_____________________________
c) CaCO3 → CaO + CO2 ____________________________
d) 2HCl + CaCO3 → H2CO3 + CaCl2___________________
e) Fe + CuSO4 → FeSO4 + Cu________________________
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25. Activity Series
____________________: a list of elements organized __________________ with which the elements undergo certain chemical reactions. Order goes from ________________________, elements will replace those _____________ them in the series.
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26. Activity Series Li Rb K Ba Sr Ca
Na ↑React with cold water and acids, replacing hydrogen. React with oxygen forming oxides. Mg Al Mn Zn Cr Fe
Cd ↕React with steam (but not cold water) and acids, replacing hydrogen. React with oxygen forming oxides. Ni Sn
Pb ↕Do not react with water. React with acids, replacing hydrogen. React with oxygen, forming oxides. H2 Sb Bi Cu
Hg ↕React with oxygen, forming oxides. Ag Pt
Au ↕Fairly unreactive, forming oxides only indirectly.

27. Practice
6) Would the following reactions take place according to the activity series?
a) Cr + H2O →____________________
b) Mg + steam → __________________
c) Au + HCl →_____________________
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28. Practice
6) Would the following reactions take place according to the activity series?
a) Cr + H2O →________________________
Mg + steam →______________________
c) Au + HCl →_______________________
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29. Ch. 8 The End!