Packet #6 Flashcards
What are two components of a buffer system
a weak acid and a weak base
Reversibility of reactions
Will be reversible if the acid is a weak acid. Will NOT be reversible if the acid is a STRONG acid.
Acid Base Neutralization
Acid gives a hydrogen to the base. Alsoways produces a salt. Salt made from metal from base and anion from acid. Usually produces water (if base acceptor has a hydroxide you will get water)
Steps for writing an acid base neutralization reaction
- Name the products (ie. water and the salt) 2. Write the product formulas 3. Balance the equation 4. Remember that if either acid or base is STRONG, the neutralization reaction is NOT reversible
Buffer components
The weak acid and the weak base
Oxidize
To take electrons from another atom
Reduce
To give electrons to another atom
Oxidation-Reduction reaction
A chemical reaction in which the oxidation numbers of atoms in reactants change
Na• + Cl → Na+ + Cl- Which oxidizes? Which is oxidizing agent? Which is oxidized?
Chlorine atom oxidizes the sodium atom The chlorine atom is the oxidizing agent The sodium atom is oxidized
Na• + Cl → Na+ + Cl- which atom reduces? Which atom is reducing agent? Which is reduced
Sodium atom reduces the cholorine atom Sodium atom is the reducing agent The chlorine atom is reduced
When an atom is oxidized, what happens to its oxidation number?
It increases
When an atom is reduced, what happens to oxidation number?
It reduces
What happens if an atom’s oxidation number goes up in a reaction
That atom has been OXIDIZED
4Fe + 3O2 → 4Fe3+ + 6O2- What is oxidation number of each individual atom in the products? Which reactant is oxidized? Which reactant is reduced?
Fe (products) oxidation number = +3 O (products) oxidation number = -2 Fe is oxidized (went from 0 to +3) O is reduced (went from 0 to -2)
Common reducing agents
Carbon Hydrogen gas (H2) Metals
Common oxidizing agents
- Oxygen Gas (O2)
- Hydrogen Peroxide (H2O2) (Peroxides in general)
- Permanganates (ex. KMnO4)
- Perchlorates (ex. KClO4)
- Hypochlorites (ex. NaClO, Ca(ClO)2
- Nitric Acid (HNO3)
- Sulfuric Acid (H2SO4)
- Halogens (F2,Cl2,Br2, I2)
Formula for Oxidation Level of an ORGANIC compound
Oxidation level = # of heteroatoms + # of double bonds + # of rings
Heteroatom
any atom in an organic molecule other than carbon or hydrogen
Triple bond in an organic molecule
counts as 2 double bonds for figuring oxidation level
How to use oxidation level in an organic reaction
If oxidation level of organic products is HIGHER than oxidation level of ORGANIC reactant than Carbon is being OXIDIZED (considered an OXIDATION rxn)
What is oxidation number of a neutral free element
Zero

Aldehyde

Amide

Amine

Carboxyclic acid

Ester

Ether

Ketone

Phenolic group
C—O—-H
Alcohol
Is addition of oxygen to an organic compoud exothermic or endothermic?
Exothermic
Is Conversion of a double bond to a single bond exothermic or endothermic?
Exothermic
Is removal of oxygen from an organic compound exothermic or endothermic?
Endothermic
Is the conversion of a single bond to a double bond exothermic or endothermic?
Endothermic
4Ni + 3O2→ 2Ni2O3
Which reactant is being reduced and which reactant is being oxidized?
Nickel is oxidized
Oxygen is reduced
2Fe + Cl2 → 2FeCl3
Which reactant is being reduced and which reactant is being oxidized?
Iron is oxidized and chlorine is reduced
Fe + Cu(NO3)2 → Fe(NO3)2 + Cu
Which reactant is being reduced and which reactant is being oxidized?
Iron is oxidized and Cu is reduced
Is adding a hydrogen to an organic compoud exothermic or endothermic? Is it an oxidqation or a reduction?
exothermic (a reduction)
Is removing a hydrogen from an organic compound an exothermic or endothermic reaction? Is it an oxidation or a reduction?
Endothermic. Oxidation