Decomposition.Morris+and+Goose

=**__Decomposition__**=

//What happens in a decomposition reaction?//
A compound is broken down into two simpler substances.

//What does the generic form of a decomposition reaction look like?//
AB → A + B

//What does an sentence equation look like?//
Nitrogen Trichloride decomposes into Nitrogen and Chloride.

//How do I change from a sentence equation to a formula?//
Lets learn how to change the following sentence equation into a formula equation:

//Nitrogen Trichloride decomposes into Nitrogen and Chloride.//

1) First, we need to know how to set up an equation. We know that on one side of an equation there are reactants, and on the other side there is the product. And we also know that the reactants, when combined, produce the product.


 * EX:** //Reactant// [produces] //Product//

2) Second, we need to figure out which substances are the reactants and what is the product of our sentence equation.

............^product^.......................................^reactant^.......^reactant^
 * EX:** **Nitrogen Trichloride** decomposes into **Nitrogen** and **Chloride**.

3) Now we need to know whether the sentence contains covalent or ionic substances. We know that covalent bonds are made up of two non-metals and ionic bonds are made up of one metal and one non-metal.

...........................................................^non-metal^...^non-metal^
 * EX:** Nitrogen Trichloride decomposes into Nitrogen and Chloride.

Non-metal + non-metal = covalent. The sentence equation above is covalent because it consists of two non-metals.

4) If the sentence equation is covalent, look at the covalent steps below. If the sentence equation is ionic, look at the ionic steps below.

__**COVALENT STEPS**__ 1) Just write what the name says


 * EX:** N3Cl  → N + Cl

__**IONIC STEPS**__ 1)Write symbols 2) Figure out charges 3) "Switcheroo" 4) Reduce

5) Balance the formula equation (I will explain how to balance formulas in the next question).


 * EX:** N3Cl  → N + **3**Cl

6) If you have the same polyatomic compounds on both sides, make sure you do not break it up!

//How do I balance an equation?//
1) Make a table under the equation

2) Count the number of atoms of each type.


 * EX:** N3Cl  → N + Cl

Side 1: N has 3. Cl has 1. Side 2: N has 1. Cl has 1.

3) If the atoms on both sides are balanced, then stop. If not balanced you have to change the coefficient.


 * EX:** N3Cl  → N + **3**Cl

4) Do not change formulas when balancing! Only change the coefficients!

Decomposition of Ammonium Dichromate

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