Double+Displacement.Morris+and+Goose

=__**Double Displacement**__=

//What happens in a double displacement reaction?//
A reaction in which the positive ion of one compound replaces the positive ion of the other compound to produce two new compounds.

//What does the generic form of a double displacement reaction look like?//
AB + CD → CB + AD

//What does an sentence equation look like?//
Silver Nitrate and Sodium Chloride react to form Sodium Nitrate and Silver 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:

//Silver Nitrate and Sodium Chloride react to form Sodium Nitrate and Silver 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.

........^reactant^..............^reactant^..............................^product^.............^product^
 * EX:** Silver Nitrate and Sodium Chloride react to form Sodium Nitrate and Silver 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.

....^metal+non-metal^...^metal+non-metal^.............^metal+non-metal^..^metal+non-metal^
 * EX:** Silver Nitrate and Sodium Chloride react to form Sodium Nitrate and Silver Chloride.

Non-metal + metal = ionic. The sentence equation above is ionic because it consists of one non-metal and one metal.

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

__**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). 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. 3) If the atoms on both sides are balanced, then stop. If not balanced you have to change the coefficient. 4) Do not change formulas when balancing! Only change the coefficients!

Copper wire in a solution of silver nitrate.

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