Unit 9 - Acids and Bases - Regents Flashcards
Definition of Acid (4)
- Arrhenius Definition - Increases H+ conc. in (aq)
- Bronsted - Lowry Definition - H+ donor to Bases
- Acids start with H
- H+ in (aq) always associates w/ H2O to form Hydronium
Definition of Coordinate Covalent Bond (2)
- Positive Ion
- Takes an unbonded PAIR of e-
Definition of Hydronium (3)
- H3O+
- Forms from Coordinate Covalent Bond
- H+ in (aq) associates 1/ H2O
Definition of Base (5)
Two Definitions, 3 Things to Remember
- Arrenhius - Increases OH- concentration in (aq)
- Proton Acceptor/Electron Donor
- NOT ALL BASES HAVE AN OH GROUP
- Base = Metal + OH
- There are NO ORGANIC Arrhenius bases
Ex: NH3 is a weak Base, R - OH is not a Base (Alcohol = Organic)
Definition of Salts (4)
- Ionic Compounds
- Dissociate to form
- Positive Ions other than H+
- Negative Ions other than OH-
Definition of Electrolytes
2 Definition, 4 in Context of Acids & Bases
- Conductors of Electricity in H2O
- Mobile e- in Solution
- Strong Acids/Bases are Good Conductors
- bc they’re nearly 100% dissociated
- Weak Acids/Bases are not Good Conductors
- bc they do not have 100% dissociation
What are the properties of acids? (5)
- Electrolytes
- Ph < 7
- Sour Taste
- React w/ metal to produce H gas
- React w/ bases to form salt & H2O in neutralization rxn
How can acids be identified by indicators? (2)
- Causes Blue Litmus Paper to shift to Red
- Causes Phenolphthalein to shift to Colorlessness
What are the properties of bases? (5)
- Electrolytes
- Ph > 7
- AKA Alkaline
- Bitter/Chalky/Soapy/Slippery
- React w/ acids to form salt & H2O in neutralization rxn
Definition of pH (2)
- Parts of Hydrogen
- Measure of how acidic or basic a solution is
Definition of pH Scale (3)
- Numerical scale ranging from 0 to 14
- Each single decrease on scale is 10x increase H3O+/H+ (decrease OH-)
- Each single increase on scale is 10x decrease H3O+/H+ (increase OH-)
What exactly did pH measure? (3)
- H+ Concentration
- NOT STRENGTH OF AN ACID OR BASE
- STRENGTH IS DEPENDENT ON DISSOCIATION
What is the formula to determine the pH? (5)
- -log (Concentration of H+)
- 14 - (-log (Concentration of OH-)
- BC 14 = pH + pOH
- When give a % of dissociation, multiply w/ molarity
- For an acid w/ more than 1 H/OH, multiply w/ molarity
What are methods to find the pH? (3)
- Paper (Litmus) Tests (Does not Damage Sample)
- Indicator Dyes (Damages Sample)
- pH Meters
What are Paper Tests for pH? (3)
- Tests for pH
- Litmus paper and pH strips
- Treated w/ indicators that change color when exposed
What is Litmus Paper? (3)
- Red litmus turns blue in alkaline solutions
- Blue litmus turns red in acidic solutions
- Acidic/alkaline result but not a pH value
What are pH strips? (3)
- More Advanced than Litmus Paper
- Features many color zones & provides pH
- Once dipped in sample, colors are matched to a pH color chart
What are Indicator Dyes for pH? (6)
- Tests for pH
- Change color based on a certain range
- Dictates pH range
- Only accurate within a certain range indicating color change
- Functions by reacting w/ H⁺ & OH⁻
- Damages sample bc involve chemical rxns
What are pH Meters? (3)
- Tests for pH
- Tests Voltage of Electrolyte
- Converts Voltage to pH
Definition of Neutralization Reaction
Acid & Base React to form Salt & H2O
Definition of Titration
- Conc. of Acid/Base Solution can be Determined
- Need to know 3 Variables (MₐM₆ = BₐB₆)
- Burette is used (lab equipment)
What must be done if the subscripts of acids & bases are not 1:1 when titrating?
- Ma is affected by the number of H+
- Mb is affected by the number of OH-
- MaVa (Number of H+) = MbVb (Number of OH-)
What is the formula when solving for moles instead of molarity in titration?
(Number of H+) (Molesₐ) = (Number of OH-) (Moles₆)
How do you know if salt is neutral, basic and acidic?
Strong Acid + Strong Base = Neutral Salt
Strong Acid & Weak Base = Acidic Salt
Weak Acid & Strong Base = Basic Salt
