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?

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-to define decomposition reaction

-to describe the process of the composition type of

chemical reaction.-to apply the process of decomposition to

chemical reactions

-to perform correct decomposition reactions.

- by using different Plants vs. Zombies

themed games to present the concept and process of decomposition and to capture the interest of the reviewer.

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It is the separation of a chemical compound into elements or simplercompounds. It is sometimes defined as the exact opposite of a chemical synthesis.

1 Reactant Product + Product In general: AB A + B

Examples An example of spontaneous decomposition is that of hydrogenperoxide, which will slowly decompose into water and oxygen:

2 H2O2 2 H 2O + O 2 Carbonates will decompose when heated, a notable exception

being that of carbonic acid, H2CO 3. Carbonic acid, the "fizz" insodas, pop cans and other carbonated beverages, will decomposeover time (spontaneously) into carbon dioxide and water

H2CO 3 H 2O + CO 2 Other carbonates will decompose when heated producing the

corresponding metal oxide and carbon dioxide. In the followingequation M represents a metal:

MCO 3 MO + CO 2 A specific example of this involving calcium carbonate:

http://en.wikipedia.org/wiki/Chemical_compoundhttp://en.wikipedia.org/wiki/Chemical_elementhttp://en.wikipedia.org/wiki/Chemical_synthesishttp://en.wikipedia.org/wiki/Hydrogen_peroxidehttp://en.wikipedia.org/wiki/Hydrogen_peroxidehttp://en.wikipedia.org/wiki/Carbonatehttp://en.wikipedia.org/wiki/Carbonic_acidhttp://en.wikipedia.org/wiki/Carbon_dioxidehttp://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Oxidehttp://en.wikipedia.org/wiki/Calcium_carbonatehttp://en.wikipedia.org/wiki/Calcium_carbonatehttp://en.wikipedia.org/wiki/Oxidehttp://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Carbon_dioxidehttp://en.wikipedia.org/wiki/Carbonic_acidhttp://en.wikipedia.org/wiki/Carbonatehttp://en.wikipedia.org/wiki/Hydrogen_peroxidehttp://en.wikipedia.org/wiki/Hydrogen_peroxidehttp://en.wikipedia.org/wiki/Chemical_synthesishttp://en.wikipedia.org/wiki/Chemical_elementhttp://en.wikipedia.org/wiki/Chemical_compound

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CaCO 3 CaO + CO 2 A common decomposition of a chlorate to evolve oxygen

utilizes potassium chlorate as follows:2 KClO 3 2 KCl + 3 O 2

Electrolysis the decomposition of a substance by an electriccurrent.

2H 2O (l) 2H 2(g) + O 2(g) Speed up decomposition

Toxic waste Waste Fats Explosives

Slow down decomposition Anti-rust Anti-aging

Decomposition Exceptions Carbonates and chlorates are special case decomposition

reactions that do not go to the elements. Carbonates (CO 32-) decompose to carbon dioxide and a

metal oxideCaCO 3 CO 2 + CaO

In some special cases, water is also a product.

Chlorates (ClO 3-) decompose to oxygen gas and a metalchloride

2 Al (ClO 3)3 2 AlCl 3 + 9 O 2 Oxides (O 2-) decompose to an element/ compound and oxygen

gas2 PbO 2 2 PbO + O 2

Hydroxides (OH+

) decompose to a metallic oxide and waterCa (OH) 2 CaO + H 2O

Acids decompose to non-metallic oxides and waterH2SO 3 SO 2 + H 2O

http://en.wikipedia.org/wiki/Potassium_chloratehttp://en.wikipedia.org/wiki/Potassium_chlorate

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A. Ferb needs help to go to his Zen garden. In order to help his way out, youneed to perform the following questions about decomposition.

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B. Match the following plants on their correct position by predicting theproducts formed using decomposition reaction.

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C. Answer th e following questions using the game Snake and Ladder Be sureto start at number 1.

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A. Determine if the reaction is a Decomposition reaction or not. Write D

if it is a decomposition reaction and N if not.1. 2CuCl + 3O2 2CuClO3 2. Fe(OH)2 FeO + H2O 3. Al2(ClO3)3 2AlCl3 + 9O2 4. 3Ca + 2H3BO3 Ca3(BO3)2 + 3H2 5. BeO + H2O Be(OH)2 6. CO2 + H2O H2CO3 7. 2 H2O 2 H2 + O2

8. 2Al + Fe2O3 Al2O + 2Fe 9. 2 KCl(s) 2 K(s) + Cl2(g) 10. 2HgO 2Hg + O2

B. Perform the following Decomposition reactions and balance.1. PbO2(s) 2. AlN(s) 3. FeCO3 4. H2CO3 5. 2 KClO3 6. H2SO3 7. NaClO3 8. Ca(OH)2 9. (NH4)2CO3 10. 2 NaHCO3

C. Fill in the blanks.

Decomposition is the 1.__________ of a chemical 2.________ intoelements or 3._______ compounds. It is sometimes defined as theexact 4.__________ of chemical 5.__________.

One 6._________ 7.________ +8. ________ In general: AB 9._ + 10._

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ASSESSMENT CARDS

A.1. N2. D3. D4. N5. N6. N7. D

8. N9. D10. D

B.1. 2 PbO2(s) 2 PbO + O2 2. AlN(s) Al + N (bal) 3. FeCO3 FeO + CO2 (bal) 4. H2CO3 CO2 + H2O (bal) 5. 2 KClO3 2 KCl + 3 O2 6. H2SO3 SO2 + H2O (bal)7. NaClO3 2 NaCl + 3 O2 8. Ca(OH)2 CaO + H2O (bal) 9. (NH4)2CO3 2NH3 + CO2 + H2O 10. 2 NaHCO3 Na2CO3 + CO2 + H2O

C.

1. separation2. compound3. simpler4. opposite5. synthesis

6. reactant7. product8. product9. A10. B