Net Ionic Equations

Precipitation: reactions are always

double replacement

Precipitation: which substances do you break when writing complete ionic equations

soluble substances

Acids

any substance that donates H+ proton

Bases

any substance that accepts proton from an acid

any hydroxide, carbonate, bicarbonate, amine, oxide

Strong acids/strong bases are

strong electrolyes, 100% of molecules dissolve

Strong acids big 6:

HCl, HBr, HI, HNO3, HClO4, H2SO4

Strong bases

group 1 and group 2 hydroxides

Acid/base: reactions are

double replacement

Acid/base: If the base if hydroxide

the two products will always be an ionic compound (salt) and water

Acid/base: If the base is not hydroxide

just move the H+ proton

Acid/base: Don’t break up what

weak acids and weak bases, water, gases, insoluble substances

Acid/base: break up what

strong acids and strong bases, soluble ionic compounds

ous =

ite

ic =

ate

acid/base: strong acid + strong base =

water only

acid/base: phantom substances

• H2CO3 and H2SO3

• very unstable in solution, they undergo immediate decomposition

• that means don’t write as H2CO3 and H2SO3 in products

• write as:

• H2CO3 —> H2O + CO2(g)

• H2SO3 —> H2O + SO2(g)

Redox: occurs when

substance loses/gains electrons

Redox: oxidation numbers

• all uncombined elements are zero (element by itself)

• all monatomic ions are equal to their charge

• sum of all oxidation numbers in a substance equals the charge

Redox: If oxidation number increases, its

oxidation

Redox: If oxidation number decreases, its

reduction

Redox: you must balance

mass and charge (overall)

Redox: number of electrons lost in oxidation must be equal to

number of electrons gained in reduction

Redox: Half reaction method

1. assign oxidation numbers to figure out which ones oxidized and which ones reduced

2. split reaction into two parts, one showing oxidation, one showing reduction

3. balance each half reaction for mass (balance everything that’s not o, h first)

   • if you need to balance oxygen use water

   • then use H+ ions to balance excess hydrogen

4. balance each half reaction for charge by adding electrons

5. use LCM to balance electrons between 2 reactions

6. combine 2 halves, cancel out what you can on each side

Redox: For balanced basic solutions, add enough OH- to

turn all of the H+ into water