ACS EXAM

isoelectronic

same number of electrons

dipole moment

goes to the more electronegative element

paramagnetic

has unpaired electrons

AB2

linear. 180

AB3

trigonal planar. 120

AB2E

bent. <120

AB4

tetrahedral. 109.5

AB3E

trigonal pyramidal. <109.5

AB2E2

bent. <109.5

AB5

trigonal bipyramidal. 120, 180, 90

AB4E

seesaw. <120, <180, <90

AB3E2

T-shaped. <180, <90

AB6

octohedral. 90

AB5E

square pyramidal. <90

AB4E2

square planar. <90

atomic radius

increases down and left

electronegativity

increases up and right

ionization energy

increases up and right

quantum number n

principal quantum number. size. 1,2,3...

quantum number l

angular momentum. shape. n-1

(n=1, x=0; n=2, x=0,1)

quantum number m(l)

magnetic. orientation. -l to l

(l=2, x=-2,-1,0,1,2)

quantum number m(s)

spin. either +1/2 or -1/2

covalent bond

share an electron pair

ionic bonds

between positive and negative ions

exceptions to electron configuration

29Cu: (Ar)4s13d10

24Cr: (Ar)4s13d5

42Mo

47Ag

AB2 hybrid

sp

AB3/AB2E hybrid

sp2

AB4/AB3E/AB2E2 hybrid

sp3

AB5/AB4E/AB3E2 hybrid

sp3d

AB6/AB5E/AB4E2 hybrid

sp3d2

bond strength

single>double and single>double

isomer

different arrangement of the exact same atoms in a molecule

sigma and pi bonds

single= 1 sigma

double= 1 sigma and 1 pi

triple= 1 sigma and 2 pi

The structure of the CO3^2- ion can be described in the Lewis formulation by these structures. this mean that:

the CO3^2- ion exists in only one form: an average of the three principal structures shown

resonance structure

multiple Lewis structures collectively describe a single molecule. describe molecules that have multiple electron dot formulas

percent mass

molecular mass/total mass x 100

vapor pressure is affected by

temperature

solubility ____________ with temperature

increases

molarity

moles of solute/liters of solution

molality

moles of solute/kg of solvent

equation for freezing point/boiling point

deltaT= K(f) x mass

osmotic pressure equation

pi= molarity x R constant x temperature

heat equation

heat = specific heat x mass x temperature change

vaporization is ______________ while condensation is _______________

endothermic

exothermic

ideal gas law equation

pressure (atm) x volume (L) = n (moles) x 0.08206 x temperature (K)

more negative delta H of formation is more ___________

exothermic

freezing has a ________ in entropy

decrease

theoretical yield

amount formed if all the limiting is used

S/I: Group 1

soluble

S/I: C2H3O2, NO3

soluble

S/I: Cl, Br, I

soluble (except Ag, Hg2, Pb)

S/I: SO4^2-

soluble (except Ca, Sr, Ba, Ag, Hg2, Pb)

S/I: CO3^2-

insoluble (except group 1 and NH4)

S/I: PO4^3-

insoluble (except group 1 and NH4)

S/I: S^2-

insoluble (except group 1 and NH4)

S/I: OH-

insoluble (except group 1, Ca, Sr, Ba)

sublimation

solid to gas

liquification

solid to liquid

vaporization

liquid to gas

condensation

gas to liquid

molecular solids

soft, low melting point, poor conductor of heat and electricity

supersaturated solutions

precipitate forms

-delta H; +delta S

-delta G; spontaneous

+delta H; -delta S

+delta G; nonspontaneous

-delta H; -delta S; low temperature

-delta G; spontaneous

-delta H; -delta S; high temperature

+delta G; nonspontaneous

+delta H; +delta S; low temperature

+delta G; nonspontaneous

+delta H; +delta S; high temperature

-delta G; spontaneous

rate law

rate= k (A)^m (B)^n (C)^p (reactants)

units of zero order

M/s or mol/L-s

units of first order

1/s or s^-1

units of second order

1/M-s or L/mol-s

zero order

rate= k

(At)= -kt + (Ao)

first order

rate= k (A)

ln(At)= -kt + ln(Ao)

second order

rate= k (A)^2

1/(At)= kt + 1/(Ao)

half life formula

t= [tln2] / [ln(No/Nt)]

zero order half life

(Ao)/2k

first order half life

0.693/k

second order half life

1/ k(Ao)

to increase rate constant, you can:

decrease activation energy

increase temperature

add catalyst

arrhenius equation

K= Ae^ [-E/RT]

rate constant increases with _____ of temperature

increase

a catalyst can:

change the mechanism of the reaction,

lower activation energy required,

disappear and reappear later in reaction,

increase the rate

what makes an equation be at equilibrium

reactants form products as fast as products form reactants;

opposing reactions at equal speeds

equilibrium constant equation for aA + bB -- cC + dD

Kc= ([C]^c x [D]^d)/ ([A]^a x [B]^b)

the equilibrium constant can predict:

direction of reaction,

extent of reaction,

amount of reactants remaining at equilibrium

increase pressure/decrease volume

shift equation toward side with lower moles

decrease pressure/increase volume

shift equation toward side with higher moles

increase products/decrease reactants

shift equation to left

decrease products/increase reactants

shift equation to right

find k with delta g

lnk= -delta G/ RT

delta g equation

delta g= delta h- t x delta s

oxidation rules order

1. free elements= 0

2. total sum is charge

3. group 1= +1; group 2= +2

4. F= -1

5. H= +1

6. O= -2

7. group 17= -1; group 16= -2; group 15= -3

oxidation equation

Fe--- Fe^2+ + 2e-

reduction equation

Cu^2+ + 2e- --- Cu

oxidizing agent

gets reduced. on left of equation. high E is better

reducing agent

gets oxidized. on right of equation. low E is better

cell potential equation

Ecell = E cathode - E anode

current/coulombs equation

coulombs= amperes x seconds

nernst equation

E= Ecell - (0.02569/n) lnQ