# Test 1: Definitions Flashcard

 Accuracy
 agreement between measured and true or accepted values
 Precision
 reproducibility between replicate measurements
 Determinate Error
 Error that can be avoided or corrected
 Indeterminate Error
 Truly random error; inherent uncertainty in measurements.
 weight
 attraction of earth
 mass
 for required for acceleration
 Molarity
 1 mole in 1 liter solution
 density
 specific gravity, grams/mL
 Formality
 contains 1 formula weight in 1 liter solution
 wt%
 weight/wt of vol*100
 vol%
 Vol/Vtot*100
 wt-vol %
 wt/vol soln *100
 milligram %
 mg/100mL
 Equivalent
 amount needed to react with 1 mole of reactant
 Normality
 1 Eq/liter
 Sig figs
 # of digits required to express a result consistent with given or measured precision
 Exp prop error
 sy/y=z(sa/a)mult ratio by exponent, mult by answer
 Log prop error
 sy=.434(sa/a)
 antilog prop error
 sy/y=sa/.434divide by .434 the mult by answer
 confidence interval of the mean
 a range with a certainty of containing the true valueu=x+-tSx=x+-ts/sqrt(n)
 F-test
 comp 2 data setsFcalc=s2^2/s1^2Fcalc>1 big always on top
 t-test
 |x1-x2|/sqrt(Sx1+Sx2)=tcalc
 Qtest
 toss out data|x-xnear|/|xhi-xlo|=Q
 average deviation
 |sumation xi-x|/n
 relative deviation%ppt
 relative to mean for specific point|xi-x|/x
 relative average deviation%ppt
 avg dev/x*100
 Relative std dev%ppt
 s/x*100
 coeff of variation
 same as rel std dev in %s/x*100
 Std error of mean
 Sx=s/sqrtnalways < s
 avg error
 error referenced to true valuesumm xi-xtrue/n
 rel error%ppt
 xi-xtrue/n
 rel avg error%ppt
 avg error rel to true valavg err/xtrue*100
 Le chatelier
 effects for concentration pressure and temperature change in equillibrium
 charge balance
 total charge of soln must be neutral. include H and OH
 Mass Balance
 For particular type of species, the sum of the added amounts must be equal to the sum of all the possible forms in solution
 complexation
 solubility begins to increase after a certain concentration due to formation of complexes.
 Activity
 A=y[C]concentrations are really the Activity
 decrease effective charge (effect on A)
 decrease
 DHLL
 log y=-.5085zi^2sqrt(u)
 Ionic strength
 u=1/2(summCizi^2)
 Ion strength effects# ions increase
 strength increase
 EDH
 DHLL/1+(a*sqrt(u)/305)a is effective hydrated ion radiusa=900 for H
 colloidal
 tyndall efect – light scatteringsmall particles<100nm
 Crystalline
 inch diametersdesirable for analysis
 precipitate mech
 Nucleation followed by particle growthin a super saturated solution
 nucleation
 small aggregates form
 particle growth
 additional molecules deposit on growth nucleus
 supersaturation
 sol’n contains more solute than would be present at EQ =>precipitate
 ss and qss
 Q-SQ-S/S
 precipitate rate
 depends on SSrate-k(Q-S)^xk and x constants
 particle growth rate
 depends on ss and nucleus surface arearate=k’A(Q-S)
 rate chart
 partrate| / ) | / ) |/–/nuc ——— RSS
 coprecipitation
 when a normally soluble substance precipitates out due to adsorption or occlusion
 postprecipitation
 contamination by other insolubles