balancing chemical reactions

Single displacement involves..

A pure element reacting with a compound

Single displacement

The free element replaces one of the elements inside the compound

1. Metal displaces metal

2. Metal displaces hydrogen from an acid

3. Metal displaces hydrogen from water

4. Halogen displaces halogen

4 types of single displacement

Metal displaces metal

More reactive metal displaces less reactive metal

Metal displaces hydrogen from an acid

Metals react with acids to make a salt and frees hydrogen gas

Metal displaces hydrogen from water

Only very reactive metals can do this

a metal hydroxide and hydrogen gas

What does metal displacing hydrogen from water form?

Alkali metals

Examples of very reactive metals

Halogen displaces halogen

More reactive halogen replaces a less reactive halogen in a salt

Higher up group 17

More reactive halogens include..

Double displacement

Two ionic compounds in aqueous solution swap positive ions (cations) and negative ions (anions) to form two new compounds

1. Precipitation reaction

2. Neutralization (Acid-base) reactions

3. Gas forming reactions

4. Acid-carbonate / base displacement reactions (formation of weak electrolytes)

Four types of double displacement

Precipitation reaction

Two soluble ionic compounds in aqueous solution react to form a precipitate and another soluble compound

Neutralization (Acid-base) reactions

An acid reacts with a base to produce salt

Gas forming reactions

Initially forms an unstable double displacement product that immediately decomposes into a gas and water

Carbonic acid and sulfurous acid

Examples of unstable double displacement products

Acid-carbonate / base-displacement reactions

Reactions that drive to completion by forming a weak electrolyte or insoluble gas/water without forming a solid precipitate directly

Weak acid like acetic acid

Examples of a weak electrolyte

Combustion

CHO rule (always go in order)

Count the carbons in your fuel and put that number in front of CO2

C - Carbon

Take all the hydrogens, divide by 2, and put it infront of H2O

H - Hydrogen

Count all the oxygen on the product side. If even, divide by 2. if odd, use fraction trick

O - Oxygen

1. Count the capital letter

2. Parenthesis rule

3. Name ending

4. 3-Element compound rule

How to identify polyatomic ions

Monatomic

Only 1 capital letter

Polyatomic

2 capital letters

..the inside of the parenthesis is a Polyatomic ion.

If you see a formula with a parenthesis around a group of elements..

Single element from the periodic table

-ide

more oxygen

-ate

less oxygen

-ite

polyatomic with oxygen

-ate or -ite

..it must contain a polyatomic ion

If it has 3 or more elements..

.. a metal and a nonmetal

A basic ionic compound only has two elements..