Name: Score:
55 Multiple choice questions
Term
Put the steps for weighing by difference in the correct order
dissovle + combine two reactants
cool in ice water bath
recover product in vaccum filtration
dissolve product
cool in ice water bath
use vaccuum filtration
Cu --> Cu(NO3)2 --> Cu(OH)2 --> CuO --> Cu(SO4)2 -- 5H2O --> Cu
weigh full beaker
transfer a third
transfer half
transfer all to clean and empty flask and reweigh
the force that pushes the mobile phase through the stationary phase (gravity)1 of 55
Term
In cation exchange chromatography of an unknown, what assumptions must be made
No other cations are present in the solution
The solution must be neutral
a primary standard has a known concentration. a secondary standard is determined
relative to it.
A: paper, wood, plastic
B: gasoline, solvents, grease
C: electrical fires
as the weak acid reacts, it produces hydronium ions in water, which react strongly with the
base2 of 55 Term
define decant
hcl
carefully pour off liquid
liquid that has passe d through a filter
pour acid int o water3 of 55
Term
to convert angs trom to wavenumber
involves no loss of sampl e, can be l iquid or solid
rapid rise in pH is pick ed up by indic ator
convert to g (divide b y 1000 ) and divide b y molar mass
multiply by 1e-8
divide the answer by 14 of 55 Term
Calculate the mass of NaOH(s ) that mus t be dissol ved in e xactly 1L of solution so that 32.00 mL of
this solution is requir ed to titrate to the equiv alence point a solution containing 0 .5453 g of a
diprotic acid with a molar mass of 142.4 g/mol.
Molar mass of NaOH = 39.997 g/mol
explain the s teps!
not all zinc was removed
Failing to evapor ate all water out of the e vapor ating dish in the final step
Overhe ating of metallic copper resulting in the forma tion of copper oxides
find the mol s of acid b y dividing the mass by the mol ar mass
find the concentration of the acid u sing the specifie d equivalence point
turn this into mols of NaOH b y multiplying b y the volume of NaOH pr ovided (it's 1 so you
don't have to do anything)
multiply by 2 bec ause the acid is diprotic
multiply by the mol ar mass to get grams of NaOH
Only (n+1) weighings are nee ded
Balance is not zeroed bet ween weighings
It does not matter if exactly the same amount is weighe d int o each flask (and it may be
bene ficial )
find mol s of known (Na OH)
divide b y two to get the mol s of acid
find the concentration of the acid b y dividing the mol s by the volume of solution nee ded
to reach the endpoint . This is the concentration of the acid
multiply the concentration b y the volume of the flask to get mols
divide the mass of the acid b y the mol s to get the mol ar mass5 of 55 Term
how to convert ppm to mol/L
convert to g (divide b y 1000 ) and divide b y molar mass
multiply by 1e-8
divide the answer by 1
rapid rise in pH is pick ed up by indic ator
involves no loss of sampl e, can be l iquid or solid6 of 55
Term
who is the visibl e light series named after
Rydber g
Paschen
Balmer
Lyman7 of 55
Term
Following an equa tion, you are given the concentr ation of copper . What is the mass of Na2S (in
the same r atio) that mus t be added to 10L of solution to precpit ate copper ?
multiply concentration b y volume
multiply by molar mass
multiply by 1e-8
divide the answer by 1
involves no loss of sampl e, can be l iquid or solid
Cu --> Cu(NO 3)2 --> Cu(OH)2 --> CuO --> Cu(SO4)2 -- 5H2O --> Cu8 of 55
55 Multiple choice questions
Term
Put the steps for weighing by difference in the correct order
dissovle + combine two reactants
cool in ice water bath
recover product in vaccum filtration
dissolve product
cool in ice water bath
use vaccuum filtration
Cu --> Cu(NO3)2 --> Cu(OH)2 --> CuO --> Cu(SO4)2 -- 5H2O --> Cu
weigh full beaker
transfer a third
transfer half
transfer all to clean and empty flask and reweigh
the force that pushes the mobile phase through the stationary phase (gravity)1 of 55
Term
In cation exchange chromatography of an unknown, what assumptions must be made
No other cations are present in the solution
The solution must be neutral
a primary standard has a known concentration. a secondary standard is determined
relative to it.
A: paper, wood, plastic
B: gasoline, solvents, grease
C: electrical fires
as the weak acid reacts, it produces hydronium ions in water, which react strongly with the
base2 of 55 Term
define decant
hcl
carefully pour off liquid
liquid that has passe d through a filter
pour acid int o water3 of 55
Term
to convert angs trom to wavenumber
involves no loss of sampl e, can be l iquid or solid
rapid rise in pH is pick ed up by indic ator
convert to g (divide b y 1000 ) and divide b y molar mass
multiply by 1e-8
divide the answer by 14 of 55 Term
Calculate the mass of NaOH(s ) that mus t be dissol ved in e xactly 1L of solution so that 32.00 mL of
this solution is requir ed to titrate to the equiv alence point a solution containing 0 .5453 g of a
diprotic acid with a molar mass of 142.4 g/mol.
Molar mass of NaOH = 39.997 g/mol
explain the s teps!
not all zinc was removed
Failing to evapor ate all water out of the e vapor ating dish in the final step
Overhe ating of metallic copper resulting in the forma tion of copper oxides
find the mol s of acid b y dividing the mass by the mol ar mass
find the concentration of the acid u sing the specifie d equivalence point
turn this into mols of NaOH b y multiplying b y the volume of NaOH pr ovided (it's 1 so you
don't have to do anything)
multiply by 2 bec ause the acid is diprotic
multiply by the mol ar mass to get grams of NaOH
Only (n+1) weighings are nee ded
Balance is not zeroed bet ween weighings
It does not matter if exactly the same amount is weighe d int o each flask (and it may be
bene ficial )
find mol s of known (Na OH)
divide b y two to get the mol s of acid
find the concentration of the acid b y dividing the mol s by the volume of solution nee ded
to reach the endpoint . This is the concentration of the acid
multiply the concentration b y the volume of the flask to get mols
divide the mass of the acid b y the mol s to get the mol ar mass5 of 55 Term
how to convert ppm to mol/L
convert to g (divide b y 1000 ) and divide b y molar mass
multiply by 1e-8
divide the answer by 1
rapid rise in pH is pick ed up by indic ator
involves no loss of sampl e, can be l iquid or solid6 of 55
Term
who is the visibl e light series named after
Rydber g
Paschen
Balmer
Lyman7 of 55
Term
Following an equa tion, you are given the concentr ation of copper . What is the mass of Na2S (in
the same r atio) that mus t be added to 10L of solution to precpit ate copper ?
multiply concentration b y volume
multiply by molar mass
multiply by 1e-8
divide the answer by 1
involves no loss of sampl e, can be l iquid or solid
Cu --> Cu(NO 3)2 --> Cu(OH)2 --> CuO --> Cu(SO4)2 -- 5H2O --> Cu8 of 55
