Mr. Greco

 Chemical Reactions

Define chemical equation.
Define chemical formula.
Define reactants.
Define products.
Define arrow (-->)
Define coefficient.
Define subscript.
Which symbols represent the states of matter in a chemical equation?
Label parts:       6 CO2      +      6 H2O ------------->     C6H12O6  +   6O2
A + B ---> AB
AB  --> A + B
AB + C ---> AC + B
AB + CD ---> AD + CB
List the steps for successfully balancing chemical equations.
How do you determine the total number of atoms in a chemical formula?
What can not be changed when balancing a chemical equation?
Answers to Questions 6-10 for Balancing Chemical Equations Practice Sheet
Answers 12-16 for Final Density & Chemical Reactions Practice Sheet

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 Define chemical equation.
An equation that uses symbols and formulas as a 
shortcut to describe a chemical reaction.
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 Define chemical formula.
A shorthand way to use chemical symbols and numbers 
to represent a substance.
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 Define reactants.
The starting materials in a chemical reaction.
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 Define products.
The substances formed from a chemical reaction.
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 Define arrow (-->)
A symbol that separates the formulas of the reactants
from the formulas of the products.  It is also called
the yields sign.
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 Define coefficient.
A number that is placed in front of a chemical symbol or formula. 

If there is no coefficient, only one atom of that
element is present.
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 Define subscript.
A number written below and to the right of a chemical symbol in a formula.

If there is no subscript, only one atom of that element is present.
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 Which symbols represent the states of matter in a chemical equation?
(s)	=	solid

(l)	=	liquid

(g)	=	gas

(aq)	=	aqueous (dissolved in water)
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 Label parts:       6 CO2      +      6 H2O ------------->     C6H12O6  +   6O2
Reactants: CO2 (Carbon Dioxide) & H2O (Water)

Products:       C6H12O6 (Sugar) & O2 (Oxygen)

Yields (Arrow):  -------->   

Coefficients: The 6 in front of CO2.
              The 6 in front of H2O.
              The 1 in front of C6H12O6.
              The 6 in front of O2.

Subscripts: The 2 below O in CO2. 
            The 2 below H in H2O. 
            The 6 below C, the 12 below H, and the 6 below O in C6H12O6.

            The 2 below O in O2.
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 A + B ---> AB
Synthesis
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 AB  --> A + B
Decomposition
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 AB + C ---> AC + B
Single Replacement
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 AB + CD ---> AD + CB
Double Replacement
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 List the steps for successfully balancing chemical equations.
1. Write a chemical equation with the correct symbols and formulas.

2. In a table, rewrite the # of atoms of each element on each side of the  
   arrow.

3. Balance the atoms by using the COEFFICIENTS.

4. Check your work by counting atoms of each element.
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 How do you determine the total number of atoms in a chemical formula?
Multiply the coefficient by the subscript!
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 What can not be changed when balancing a chemical equation?
Subsripts!
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 Answers to Questions 6-10 for Balancing Chemical Equations Practice Sheet
6. 2Al + 3CuSO4 --> Al2(SO4)3 + 3Cu

7. Mg(OH)2 + 2HCl --> MgCl2 + 2H2O

8. BaCl2 + H2SO4 --> BaSO4 + 2HCl

9. 4P + 5O2 --> P4O10

10. 2KClO3 --> 2KCl + 3O2
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 Answers 12-16 for Final Density & Chemical Reactions Practice Sheet
12. 4Al(s) + 3O2(g) -> 2Al2O3(s)

13. Fe2O3(s) + CO(g) -> 2Fe(l) + 2CO2(g)

14. 2C2H6 + 7O2 -> 4CO2 + 6H2O

15. 3H2 + N2 -> 2NH3

16. 2H2O2 -> 2H2O + O2
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