Chemical Reactions Flashcards
Physical Changes
Substance/Composition doesn’t change
IMFs change but bonds aren’t broken
Chemical Changes
New substance is formed
Breaking of chemical bonds
Evidence of a Chemical Change
Formation of gas
Energy change
Color Change
Formation of precipitate
Strong Acids
HNO3, HClO3, HClO4, HCl, HBr, HI, H2SO4
Dissolution
Dissolving of a solute in a solvent
Can be physical because it’s reversable
Can be chemical because bonds are broken
Titration
A solution of a known concentration is combined with a solution of an unknown concentration to determine the amount of moles in the unkown
Titrant
Solution in the buret
Usually the solution of known concentration
Analyte
The solution in the flask (unknown)
Equivalence point
The point where the titrant has completely reacted with the analyte
End point
When the indicator changes color and the analyte is fully reacted
Titration Curve
Used to determine the equivalence point
Point with the greatest slope indicates the volume of titrant needed to react with the analyte
Types of Chemical Reactions
Acid-Base Reactions
Oxidation-Reduction Reactions
Precipitation Reactions
Acid-Base Reactions
Transfer of one or more protons from the acid to the base
Conjugate Base
Substance formed after the proton is removed
Conjugate Acid
Substance formed when the proton is added
Conjugate Acid-Base Pair
One substance on the reactants side and one substance on the products side that differ by only a proton
Redox Reactions
Involves the transfer of electrons between reactants
indicated by rust and corrosion
Substance losing electrons is oxidized and substance gaining electrons is reduced
OIL RIG
Rules of Assigning Oxidation Numbers
- Monoatomic ions = its charge
- Hydrogen = +1 (unless it’s a metal hydride like NaH where it’s -1)
- Oxygen = -2 (except for peroxides like H2O2 where it’s -1 and in some compounds it’s positive)
- Elemental form of an atom = 0
- Neutral compounds = sum is 0
Polyatomic ions = sum is its charge
Precipitation Reactions
Usually double replacement reactions that produce a solid product
Arrhenius Acids
Increase H+ in water
Arrhenius Bases
Increase OH- in water
Bronsted-Lowry Acid
Donates a proton H+
Bronsted-Lowry Base
Accepts proton
Must have a lone pair to accept H+
Amphiprotic
Can act as a acid or a base depending on what is reacting
