Solubility Flashcards
What’s molality in concentration?
It’s described as moles of solute/mass of solvent
What’s Ksp and how is it written?
It’s solubility of product and it can be calculated as Ksp = [Products] with coefficients becoming exponents i.e. same as any other equilibrium constant
CaCl2 (s) > Ca2+ (aq) + 2Cl- (aq)
Ksp = [Ca2+][Cl-]^2
What does it mean by unsaturated, saturated and supersaturated?
Unsaturated: When less solute is dissolved than the maximum possible amount
Saturated: when maximum amount of solute is dissolved
Supersaturated: when more than maximum amount of possible solute is dissolved
What’s common ion effect?
It says that presence of an ion in solution will decrease solubility of compounds containing that ion i.e. Na+ in water will decrease the solubility of NaCL
What’s salt?
Any substance made of anions and cations
What’s auto-ionization or self-ionization of water?
It’s two water molecules combining to form H3O+ (cation) and OH- (anion)
How come NaCl dissolved in water doesn’t go back to solid on its own?
Water creates a hydration shield around Na+ and Cl- ions that prevents them from interacting with each other
What’s Lewis and Brønsted-Lowry definition of Acids and Bases?
Lewis:
Acid accepts an electron pair
Base donates an electron pair
Brønsted-Lowry:
Acid donates a proton
Base accepts a proton
What does acid and base become?
Acid makes conjugate base and base makes conjugate acid
H3PO^4 + H2O 🔛 H2PO4- + H3O+
H3PO4 = Acid
H2O = Base
H2PO4- = Conj. Base
H3O+ = Conj. Acid
What’s the role of equilibrium constant Keq?
They help is quantify whether a reaction will go forward or backward
Keq can be described as
Keq = [Products] / [Reactants]
What is not included in calculating equilibrium constant?
Water concentration is not included in the calculations
What is included in equilibrium constant?
Only aqueous species i.e. Kw = [Products] (not reactants if there’s only water)
How to calculate pH from concentration and concentration from pH?
pH = -log ([H+]) or -log ([H3O+])
10^-pH = [H+]
