Exam 2 Flashcards
(35 cards)
What are the rules for manipulating the equilibrium constant?
- Reverse rxn = 1/k
- multiply rxn coefficients = K raised to multiplier
- Add two rxns = multiply k’s
What affects equilibrium/K?
Temperature
What does not affect equilibrium/K?
- Presence of catalysts
- Adding non-agents
- Solids and pure liquids
- Changing P/V
- Differing initial concentrations
How does change in T affect exothermic and endothermic rxns differently?
Endothermic- K gets larger (right shift) when T increases and vise versa
Exothermic- K gets smaller (left shift) when T increases
How do you find delta G not of a rxn?
Products minus reactants (multiplied by stoicheometric coefficient)
How do you derive delta G equations from equation sheet?
See equation sheet
How do you write a losing of 4 neutrons?
4 as coefficient, not as numerator
Binding energy remember
Do not forget to account for electrons (if applicable)
nucleons - nucleus
Atomic mass - need to subtract electrons
Nucleic mass- no subtraction necessary
Meaning of A = kN
A = activity (disintigrations/s) k = k value calculated from half-life equation N = number of nuclei present, found from atomic mass and Avogadro's number
pKa equation
pX = -logX
pKa = -logKa Ka = 10^-pKa
Meaning of Sv and Gy
Sv = Sievert = effective exposure. Found by multiplying Gy by RBE for that specific type of radiation Gy = Joules/Kg tissue mass
Acid strength trends
Binary acids - increase going down the row
Oxoacids - increase going up the row (except F)
Within oxoacid series - the more O present, the stronger the acid
The stronger the acid, the weaker the conjugate base
Factors affecting acid strength
Polarity- the more polar, the stronger the acid
Electronegativity- the more electronegative, the stronger the acid
Stability of conjugate base- the more stable the conjugate base, the stronger the acid
Strength of conjugate base- the weaker the conjugate base, the stronger the acid
Factors affecting base strength
Electron donating group present- strengthens base
Electron withdrawing group present - weakens base
The stronger the base, the weaker the conjugate acid
pH equations
pH = -log[H+}
[H+] = 10 ^-pH
pH +pOH = 14
[H+][OH-] = 1x10E-14
pOH equations
pOH = -log[OH-] [OH-] = 10^-pOH
Classify weak or strong: HI
strong
Classify weak or strong: HBr
strong
Classify weak or strong: HCl
strong
Classify weak or strong: HClO3
strong
Classify weak or strong: HClO4
strong
Classify weak or strong: HNO3
strong
Classify weak or strong: H2SO4
strong
Classify weak or strong: HF
weak
