Chapter 7 Lecture Flashcards
characteristics of acid
- taste sour
- in contact with litmus paper; stained PINK
- reacts and dissolves with some metals
- donated H+ ions!!!!
- always or typically has H-
characteristics of bases
- taste bitter
- when in contact with litmus paper; BLUE
- feel slippery
- always donate H+ ions
- typically have -OH
conjugates
two compounds (pair) that differ by an H+
amphoteric acid
can be an acid or base; water is a specific example
equilibrium
when the rate of the forward reaction and the rate of the reverse reaction are equal
**this only refers to the RATES of the reactions, not the CONCENTRATIONS!
equilibrium constant
Keq = [C]c[D]d/[A]a[B]b
or = [products]/[reactants]
this equation helps us figure out whether reactants or products are being favored within the equation
specific phases to the equilibrium constant
- SOLIDS are always omitted; solid concentrations never change
- SOLVENTS typically omitted; don’t change significantly
interpretation of equilibrium constants
Keq > 1 = REACTANTS < PRODUCTS
Keq < 1 = REACTANTS > PRODUCTS
Keq = 1 = REACTANS = PRODUCTS
Le Chatelier’s principle
when a reversible reaction is pushed out of equilibrium, the reaction responds to reach a new equilibrium
what changes can disrupt an equilibrium?
changes in either:
- concentration
- temperature
- pressure
what happens if 2 water molecules react with each other?
creation of both hydronium and hydroxide ions
what is the ionization constant of water?
Kw = [H3O+][OH] = 1.0 x 10^-14
how is the pH scale determined?
determined through the amount of hydronium (H3O+) ions we have within our solution is:
- acidic
- basic
- neutral
pH equation?
pH = -log[H3O+]
what is the range of the pH scale?
- scale from 0 - 14
- ACIDIC: x < 7
- NEUTRAL: 7
- BASIC: x > 7
describe acid strength
the STRONGER THE ACID = GREATER H3O+ PRODUCTION = LOWER PH
*strong acids = completely ionize
*weak acids = partially ionize
what is the acidity constant? (example)
- very similar to the Keq (equilibrium constant equation)
- products/reactants
- the LARGER the Ka = the STRONGER the acid
*correlates wtih pKa = the LOWER pKa = STRONGER the acid
base strength
the STRONGER THE BASE = the GREATER -OH PRODUCTION = HIGHER PH
*weak bases only partially ionize
neutralization
when an acid and base react to form salt and water
*if proper amounts are added, this will make the solution NEUTRAL (lol get it cause “neutralization”)
titration
lab technique used to determine CONCENTRATION of an acid or base solution
how does titration work specifically?
- for starters, having an UNKNOWN ACID CONC.
- can use a BASE - KNOWN CONCENTRATION
- to DETERMINE ACID CONC.
titration end point
adding enough BASE (known conc.) to consume all ACID (unknown conc.)
*moles of base = moles of acid
buffer
solution that is resistant to a pH change when a small amount of acid and base is added
how are buffers produced?
weak acid and conjugate base
when are buffers most resistant to pH changes?
when pH = pKa of ACID
why are buffers important?
if our body is out of buffers, our physiological range(7.35 - 7.45); enzymes are not able to function
