molar concentration sheet

Transcription

molar concentration sheet
ffimffim
J
$oluflons
Knowledge of the properties and uses of solutions is important in the study of chemistry.
Many substances used in laboratories are much easier to storc and use in solution form.
Many chemical reactions happen only when the reactants are in solution.
J"l
Solutes cnd Solvenfs
Solutions are homogeneous mixtures-that is, solutions are uniform throughout the
mixture on a molecular scale. The substance in solution with which the chemist is most
concerned is called the solute, the "stuff" which is dissolved. The solvent is the substance
that causes the solute to be dissolved and is the carrier for the solute. Most common
solutions use water as the solvent and are called aqueous solutions.
Solute Solvent
Examples
gas
gas
alr
gas
liquid
ammonia solution, carbonated beverages, 02 in water
gas
solid
hydrogen in palladium (an element)
liquid
liquid
antifreeze, wine, beer
liquid
SOIid
dental amalgam (mercury in silver)
solid
liquid
salt water, sugar solutions
solid
solid
metal alloys (silver in gold)
J.2 Concenfrqfion of Solutions
Whether you are cooking in the kitchen, making a garden spray or analyzing samples in
a medical laboratory. solutions of known concentrations are being used. Rather than
determine the mass of specific quantities of reactants for chemical reactions, it is more
convenient to dissolve the chemicals to make solutions of known concentration. The
chernicals may then be dispensed by measu ring specific volumes of solution.
The concentration of a solution describes the amount of solute relative to the volume
of solution. A solution of high concentration is called concentrated, while a solution of
low concentration is said to be dilute. A solution may be diluted by increasing the
amount of solvent in the solution.
In order to determine the arnount of solute in a measured volume of solution, the
concentration of the solution and the solution volume must be known. Concentrations of
solutions are commonly rneasured in terms of molar concentration. The molar
concentration of a solution is defined as the number of moles nf solute dissolved in a liter
of solution. This definition is commonly expressed as the formula:
molar concentration of solute =
amount of solute in moles
Of L; =
volume of solution in liters
n
VL=
mol
The units for molar concentration are mol/L. When the single word concentration is used
in the text, it is assumed thal molar concentration is meant.
2,i,6
Ljt-lr J
Solutions
J.3 Exercises Concentrqtion of Solutions
L. Detine the followi*g terrns:
a. solute
b. solvent
c. solution
cl. concentration
2. What units are used" to measlrre molar concentratian?
J"4 Solufion Problem'Solving
As with problems in Units F and G, solution problems can be solved by either of two
methods: by equations (Method r) or by the conversion-factor technique (Method 2). The
examples and problems that follow show many applications of, and the convenience of,
working with solutions. The examples shown will be solved by boih calculation methods.
Method 1
Equation Method: only two formulas with their variations are needed to
solve most solution problems (see Flct;nE I1). Start with the given amount and use
the equations appropriate to determine the unknown quantity.
Method 2
Conversion Factor Method: many people find it easier and faster to use
molar -mass and molar concentration in such a way that the ratios allow the units to
cancel. This way the multiple calculations involved in doing solution problems can
be set up as one problem and the units can be used to double-check the accuracy of
the setup (see Frcunr I2).
FIcunn|1 EquationProblem-Solving
Flowchart
Equations
{s)
MASS
M(s/mol)
NM
and
C
!
volume
*llM
of solution
V
moles
Note: lf the Equation
Method is used, the
formula should be
verified each time
by substituting the
correct units into the
formula and making
sure that the correct
units are obtained in
the answer.
C
I
V
molar
concentration
Cv
P=
[=
T=
Solutions
UNtr
J
2l*7
Flcunr
12
c*nversion f-actor Prohlem-$olving
Flowchart
R"atios
Molar Concentration
# mol
L
:
= ffiol
1L
volume
1L
mol
of solution
# mol
moles
Molar Mass
rnol
g
#o
lmol
v-t4
*v
v
ldeal Gas Law
PV = nRT
molar
concentration
1 mol
'-.
tTlol
#g =
P=
VT
Cqlculqring Concentrqtion frcm Moles ond Volume
If 0.S00 mol of table salt, NaCl, is dissolved to give 500. mL of a laboratory solution, what
is the molar concentration of the solution?
In this case the definition for molar concentration is used:
c = !v -
o'9oomol
0.500
L = 1.80
mol
L
Cqlculoring Concenlrotion from Moss ond Volume
An antacid solution may be prepared by dissolving 15.0 g of sodium bicarbonate (baking
soda) in sufficient water to make 250. mL of solution. Determine the molar concentration
of the antacid solution.
Method
t:
nru"Hco3
m
M
C
n
V
Methodz: C
:: 1s.adNaHCO.
x
1sP4
:0.1zemor
84.01g/mol 0,179 mol
-r,
0.250 L
1 mol NaHCOu
84.0t9(t-taUCO*
1
X
o"25oL =
mol
L
a.714ry
NaHCou
Regardless of what method you choose, be sure to follow the step-wise sequence shown
on the flowchart.
Colculofing lVloss from Volume ond Concenfrsflon
This type of calculation is most commonly used by chemists and technicians in preparing
solutions of known concentration"
What mass of washing soda, IrlarCO3 . L0 HrO, is necessary to make 400. mL of 0.b00 mol/L
solution?
24.'j
Unm
J
Solutions
Methocl
l:
nna2co316Frzo
= Cv = 0'500 Y
-
mNa2co3toFi2o
= nM =
x 2S6'19 -gryd
=
Meihod
2r
rn61sr663r0!-rzo
0'200 rya(
57.2
= 0.4a0]-
"
O.40OE
= 0'200
mol
gof Na2CO3'10HzO
*+P
" '::#
= 57"2gof Na2CO3'10H2O
Colculoting Volume from Mqss ond Concentrqfion
Soclium hydroride. conmonlv kno'uvn as caustic soda, has many uses in the laboratory
and in industry. What volume of 0.600 mol/L NaOH can be prepared frorn 4.8 g of solute?
Methodl:
nNusH
=
fi =
o'12 Por
n ^#fu,=o.12mol
o.2o L of solution
c = o.oooffi1r/L =
n,
lvfethocl2: VNaoH = 4.8.4iNaoH * .S**
VNaoH=
1L
40.00paNaOH 0.600po|-NaOH
J.5 Exercises Solufion Problem-Solving
1. Copper(Il) sulfate, an important copper salt, is used in copper electroplating cells,
and to kill algae in swimming pools and water tesen,oirs. What is the molar
concentration of an electroplating solution in which 1.50 mol of copper(Il) sulfate
are dissolved in enough water to make 2.00 L of solution?
2. Whenll.0gofglacial(pure)aceticacidisdissolvedinwatertomake2S0.mLof
vinegar solution, what is the moiar concentration of the vinegar?
3. Sociium bicarbonate is used medicinallv to counteract excess stomach acidity. How
many rnoles of solid sodium bicarbonirte would be needed to make 100. mL of a
0.660 mol/L solutiou suitabie for use as an antacid'l
4. A toilet howl cleaner may be prepared b)'mixing sodium bicarbonate (baking soda)
and socliurn hydroxide (lye). What mass of sodium bicarbonate must be added to a
2.50 L borvl to obtain a necessary 0.150 mol/L solution?
5. Sodium phosphate may be used to rernove scale deposits from a car radiator. What
volume of a 0.075 mol/L solution rvould contain the necessary 1.10 mol of sodium
phosphate to remove the radiator scales?
Sclutions
UNm
J
249
\
7I
t2
SOLUTIONS
CONCENTRATION OF SOLUTIONS
11 ,12
Concentration of Solutions
ol
The concentrationola solution describes the amount o{ solute relative to the volume of solution. A solution
be
may
A
solution
is
called
dilule.
high concentration is called concentrated, while a solution of low concenlration
dituted by increasing the amount of solvent in the solution.
ln orderto determine the amount of solute in a measured volume of solution, the concenlration of the solution
of
and lhe solution volume must also be known. Concentrations ol solutions are commonly measured in terms
dissolved
ot
solute
moles
number
of
ined
as
the
is
def
molar concentration. The molar concentralion of a solution
in a litre of solution. This definition is commonly expressed as a formula.
amount of solute in moles
volume of solution in litres
molar concentration
solute
N
tv
or
t
V
in ALCHEM, assume that
The units lor molar concentration are mol/L. when the single word concentration is used
molar concentration is meant.
Solution Problems
the many applications of and the convenience of
The examples and problems which follow serve to illustrate
need be used to answer most solution problems;
va'riations)
(with
their
formulas
working with solutions. Only two
i.e.,
n=n
n
sndc=
m_
Y
Type 1: Calculating Concentration lrom Moles and Volume
lf 0.900 mol of table salt, NaCl, is dissolved to give 500 mL of a laboratory solution, what is the molar concentration of the solution?
,^
NaCl
n
\-,
v
0.900 mol
0500
L
=
1
.80 mol/ L
G
fhe molar concentration of the table salt solution is 1.80 mol/L
Type
2: Calculating Concentration lrom Mass and Volume
An antacid solution may be. prepared by dissolving 15.0 g of sodium bicarbonate (baking soda) in sufficient
/yater lo make 250 mL of solution. Determine the molar concentration of the antacid solution
n=
Na
HCO,
n
m
m
Na HCO,
15 og
A.17 9 mol
= a.250 L
0.1 79 mol
=
ffit
The antacid solution
v
0.716 mol/L
0.716 mol/L
Type 3: Calculaling Moles from Volume and Concenlration
potassium permanganate, KMnoo, due to its oxidizing properties is an effective disinfectant. How many moles
cf KMnOo are in a 2.00 L of disintectant solution that is 0.0025 mol/L KMnO. ? (Note: One should be aware of the
other properties of KMn(J4 Detore uslng it directly as a disinfectant')
n=Cv
KMnOo
=
=
0.0025 moll L x 2.00
L
0.0050 mol
The number of moles of KMnOa required is 0.0050
Calculaior
Nole:
- ti Gi;g; iitcirtitor
for a two step problem, round off the answer lor the lirst step to lhe correct number of si9nilicant digits. Fle-enter the first-step answer into the calculator to do the second step. When done this way
the rounded off tinal answer should agreq with the answer that the teacher has'
t3
SOLUTIONS
SOLUTION PROBLEMS
l2
,
Type 1: Concentration from Moles and Volume
1.
Copper(ll) sulfate, an important copper salt, is used in copper electroplating cells, and to kill algae in swimming pools and water reservoirs.
What is the molar concentration of an electroplating solution in which 1.50 mol of copper(ll) sulfate are dissolved in water to make 2.00 L of solution?
2.
What is the molar concentration of a solution in which 0.240 mol of washing soda, NarCOs'1OHeO, is dis-
3.
lron(ll) sullate finds use in fixing colors in dyeing and in making ink.
solved in water to make 480.mL of a solution for softening wash water.
What is the molar concentration of an ink solulion that contains 0.210 mol of iron(ll) sulfate dissolved to
form 840.mL ol solution?
I
Remedial Problems
4.
Since a saturated solution of calcium chloride does not f reeze until -55 "C, calcium chloride can be used to
melt ice on roads and walks.
What is the molar concentration of a saturated solution in which 35.5 mol of CaCl, is dissolved in water to
make 5.00 L of solution?
5.
Sulfuric acid is an important laboratory reagent as well as a very important industrial chemical. One ol its
many industrial uses is an electrolyte in lead storage (car) batleries.
Calculate the molar concentration of a battery acid solution which contains 9.25 mol of
form 1.80 L of solution.
il
Ha
SO4 dissolved to
t2
SOLUTIONS
SOLUTION PROBLEMS
l4
$,
-
Type 2: Concenlration lrom Mass and Volume
1
.
A given sample of household ammonia contains 156 g of NHa(o) dissolved in water to form 2.00 L of solution.
What is the molar concentration ot the household am:-nonia'Sillulion?
2.
When
3.
What is the molar concentration of 500.mL of a solution that contains 12.7 g of swimming pool chlorinator,
1 1 .0 g of glacial (pure) acetic acid is dissolved in water to make 250rmL of vinega r solution , what is
the molar concentration of the vinegar?
Ca(OCl)r?
6,
Remedial Problems
4. Asolution forwaterproofing concrete may be prepared by dissolving 2006 of ammonium stearate in water
to make 5.00 L of solution. Determine the molar concentration of the solution.
5.
L
A car battery terminal protective coating can be prepared by dissolving 240.0 g of sodium silicate (water
glass) in water to make 250rmL ol solution. What is the molar concentration of the solution?
t6
SOLUTIONS
SOLUTION PROBLEMS
t2
1
.:
*
G
Type 3: Moles lrom Volume and Concentration
counteract excess stomach aciditY
sodium bicarbonate is used medicinally to
mol/ L solution
needed to make 100uml of a 0.660
Howmanymolesofsolidsodiumbicarbonatewouldbe
suitabre lor use as an antacid?
'
*
,
{
2
.
\
A usef ul tile and household cleaner is sodium PhosPhate
Find the number of moles of Na, POo
for use at home.
3.
(TSP)
'
in2.00Lofa0'100mol/L
Nag POo
m
A rust stain remover may be prepared by d issolving Potassiu
prepared
(aq) cleaning solution
Pe rsulf
persulfate are there in 500rffiL of a
How many moles of potassium
removing rust ila ins?
O
ate
'242
(
K2 SO5
) in wate r.
mol/ L solution suitable for
Remedial Problems
reagent, finds considerable use in cleaning
4..Hydrochloricacidinadditiontobeinganimportantlaboratory
before painting and inpttparingarticlesforgalvanizing'tinning
rust off iron and steer, in etching concrete
or electroPlating.
in 75'0 mL of 0.100 mollL hydrochloric acid cleaning
Find the number of mores of hydrogen chloride
solutton.
5.
from which many
and industrial uses' lt also is the source
common salt, NaCl, has numerous domestic
derived',
are
Naclo
and
Narsoo
N;Hco;, Narco.,
valuable sodium compounos such as r.raoH,
HowmanymolesofNaClareneededtoprepare500,mLofSaturated5'30mol/Lsolulion?
G
SOLUTIONS
SOLUTION PROBLEMS
l2
l9
e
Type
4: Calculaling Mass from Volume and Concentration
What mass c{ washing soda, NarCOr.1OHrO, is necessary to make 400 mL of a 0.0500
solution?
=Cv
= 0.0500 mol /L x 0.400 L
n
Na, CO, .1 0H, O
N", CO, .1 0H,
mol/L
=nM
O
The mass ol washing soda required is 5.72 g.
Type 5: Calculating Volume from Moles and Concentration
Vinegar is a dilute solution of acetic acid,
1.60 mol of acetic acid?
cHrcooH. what volume of 0.800 mol/L v-ineg-ar
solution conlalns
_-!_
u
cH3cooH
= o'8oo
'too*"'
mol/L
2.00
L
=
I
The volume of vinegar necessary is 2.00 L.
Type
6: Calculating Volume lrom Mass and Concentralion
Sodium hydroxide, commonlv known as caustic soda, has many uses in the laboratory and in industry. What
volume of 0.600 mol/L NaOH can be repared from 4.8 g ol solule?
n=m
NaoH M
t,
v
NaoH
t
g
40.00
=
A.12 mol
g/
mol
n
C
0.600 moV
The volume
4'8
=
L
of NaOH(uq; that can be prepared is 0.20
L.
t10
SOLUTIONS
SOLUTION PROBLEMS
12 ,13
$
Type 4z Mass f rorn Volume and Concentration
(lye)'
bicarbonate (baking soda) and sodium hydroxide
A toilet bowl cleaner may be prepared by mixing sodium
1.'
What mass of sodium bicarbonate must be added to
0.1
L;
a 2.50 L bowl to obtain a
necessary
50 mol/ L solution?
molar
along with the baking soda in ouestion 1 if the
What mass of lye (NaOH) must be added to the bowl
concentration of the lye must be 0.0/5 mol lL?
Remedial Problems
under
in water and its concentrated solution is sold commercially
3 .r Sodium silicate, N a, Si03 , is verY soluble
the
half
and
phosphate
sodium
of
mass
equal
with an
the name of water glass' Sodium silicate may be used
for dishes and laundry'
mass of sodium metaPhosPhate to prepare a water softener
10.0 L of a 0.00500 mol/L water softening solution?
What mass of sodium silicate is necessary to prepare
4.
A hydrate ol sodium thiosulfate known
as hypo(NarSrO.'SHzO)
is used as
$
a fixer in photography because
it readily dissolves silver compounds'
Show the calculations and list the steps'
Describe how to prepare 100rmL of a 0.120 mol/L hyposolution.
6,
SOLUTIONS
SOLUTION PROBLEMS
|.2,13
0
111
Type 5: Volume from Moles and Concentration
1.
Sodium phosphate may be used to remove scale deposits from a car radialor.
What volume of a 0.075 mol/L solution would conlain the necessary 1.10 mol of sodium phosphate to
'emove the radiator scales?
2.
A perspiration stain remover may be prepared from sodium perborate trihydrate (NaBOr.HzOz.3HrO).
Jalculale the volume of 0.600 mol/L perspiration stain remover that would be prepared lrom 0.300 mol ot
sodium perborate trihydrate.
Remedial Problems
3. Awatersolution of sodium hydroxide, known as caustic soda, is useful for dissolving grease and matter of
plant and animal origin.
Oalculate the volume of 0.100 mol/L caustic soda solution that contains 3.ti0 mol of sodium hydroxide
I
4.
silver nitrate is used extensively in making photographic plates and films.
What volume of 0.320 mol/L silver nitrate solution would contain 0.24O mol of silver nitrate?
5.
Sodium bicarbonate is used in baking as baktng soda, or as one of the componenls of baking powder.
Describe how to prepare 0.821 mol/L saturated solution of sodium bicarbonate using
bicarbonate.
ft
1
.64 mol ol sol6 sodium
112
soLuTloNS
12,13
SOLUTION PROBLEMS
Concentratlon
Type 6: Volume lrom Mass and
of sodium hYPochlorite; e'g'
'
l.ChlorinebleachinitssolutionlormusuallyissoldasaSto6percentsolution
as in Clorox and Purex'
g of NaOCI
solution would contain 119.2
How many ritres of 0.800 mol/L
2.
?
hardened with Paint'
very efficient cleaner for old brushes
a
makes
phosphate
A sorution o{ sodium
POn ?
f rom 126 g of Nas
creaning solution can be Dre0ared
brush
mor/L
0.700
of
what vorume
$,
with a protective coating of conprevented by painting the terminals
- Remedial Problems
3.Corrosionofbatteryterminalscanbe
centrated sodium silicate, Ndzsio3
.
240"9 ol sodium silicate
solution can be prepared from
What volume of 8'20 lnollL coating
4.
?
cleaned of
household utensils can be economically
other,nonaluminum
and
pans
lrying
Pots, kettles,
lye (NaOH)'
materials Oy using a solution ol
grease anO OaxeO-Jn'tooO
Describehowtopreparea0.l00mol/Llyesolutionusingl0.0golsolidNaoH'showcalculationsandlisl
the stePs.
@
12, 13
t
SOLUTIONS
AN OVERVIEW
SOLUTION PROBLEMS
t13
-
1.
A dilute salution of sodium bicarbonate can be used as a soothing eyewash.
disolved
what is the molar concentration of an eyewash solution which has 3.57 mmol ol sodium bicarbonate
in water to make 240'mL ol solution?
2.
remover'
Sodium bisullite and oxalic acid dissolved in water makes an effeclive radiator rust
NaHSO., is dissolved in
What is the molar concentration ol a solution in which 1206 ol sodium bisulfite,
waler to form 8.00 L of a rust removing solution?
3.
grease from engines
An all-round cleaning agent, sodium phosphate, is excellent lor removing
and
mechanical Parts.
cleaning solution
Find thenumber ol moles of sodium phosphate in 8.00 L of a 0.0125 mol/L
4.
I
certain organic impurOne ol the many industrial uses of sulfuric acid employs sulfuric acid for removing
ities lrom Petroleum.
What volume of 2.50 mol/L H2SO! solution would contain 2.00 mol of sulfuric acid?
5.
its soluSodium hydroxide (commonly known as caustic soda or lye) is used as a cleaning agent because
plant
origin'
and animal
tions readily dissolves grease and other matter of
What mass ol sodium hydroxide is required to prepare 400.mL of a 0.2(X) mol/L cleaning solution?
6.
A calcium chloride solution may be used as a grass killer'
What volume of a 1.0 mol/L calcium chloride grass killing solution could be prepared lrom 1.00 kg of
calcium chloride?
7
.
Ammonium carbonate is a suitable replacement for the aqueous solution of ammonia as a household cleaning agent because it yields ammonia readily.
Describe how lo prepare 1.00 L of a 0.450 mollL solution of ammonium carbonate. show calculations
and list the five steps followed in preparing the solution.
t
l4
I
SOLUTIONS
DILUTION
Most solutions bought lor laboratories are bought in concentrated form. Some solutions
are
concentrated form in the laboratory for later use. The bought or prepared solutions
are then
solutions of known concenlralion as required.
d
orF,
r
)
When a solution is
diluted, only lhe amounl of solvent is increased. Therefore, the number of moles
of solute:
in lhe initial (concentrated) solution is equal to the number of moles of solute in lhe finat(diluted)
solution.
i - initial
f =final
ni = nS
Civi = CFI
Sincen = Cv
The above equation may be used to solve several types of dilution problems.
Example 1:
Concentraled commercial hydrochloric acid is prepared by dissolving hydrogen chloride gas in
water. The
molar concentration of concenlrated hvdrochloric acid is 12.4 mol/L.
what volume of concentrated {38olo) hydrochloric acid must a laboratory technician
use in order to prepare
2.00 L of 0.250 mol/L HCt13q;?
Civi = CFt
12.4 moUL x vi = 0.250 mol/L x 2.00 L
v; =0.250 mol/L x 2.00 =L o'0403 L
ir,.4 r"r/LThe volume of concentrated hydrochloric acid required is 40.3 mL.
Example 2:
concentrated (glacial) acetic acid is 99.5% pure and has a concentration ol 17.4
mol/1.
What is the molar concentration of a 5olo vinegar solution prepare-d from concentrated
acetic acid if 200 mL of
concentrated acetic acid is diluted to fill a 4.00 L container of vin-egar?
Civi = Cflf
17
0.870 rnoll
L
.4 mol/L x 0 .20O L =
l7 .4 mol I L x 0.200
4.00
Cr x 4.00
L
L
Cg
L
Ihe molar concentration of the vinegar solution is 0.BZO mot/L.
Molar Concentration of
Some Concentrated Solutions
irt
;:'.::i
t'.i.::r'
UCllaq)
H3 PO4 (aq)
HNO3 (aq)
CH, COOH(rq)
H2 SO4 (aq)
N H. (aq)
3\o/o
8 5o/o
690/o
99.5 o/o
17
I 4 "/o
tT .O mol/ L
28
1
o/o
12.4 moll
L
I 4 .t mot/ L
15.4 mol/L
.4 mol/
L
4.8 mol/ L
QA
SOLUTIONS
DILUTION PROBLEMS
l4
ThefollowingtwopagesofdilutionproblemswereadaptedfromjnformationobtainedlromTheFormulaBook
Robert C' Weast'
tne CRC Handboii iici"*itstry and Phvsics edited by
by Norman Stark and liom
l.oneoftheusesofmethanol,cH3oH(alsoknownaSmethy]alcohol,woodalcoholandmethylhydrate)'
of
tn pure form methanol has a molar concentration
in diluted form is a windshield *asn")-antlrreeze.
24'7 mollL
10'0 mol/L
chemistry and Physics a srudent preoared 8'0 L ol was necesJslng a table rrom rhe cRc Handbook ol
methanol
ol
volume
What
antltreeze goo7t tor-30"1;'
aqueous methanol as windshielO wasnei
a"ry to prepare the antifreeze solution?
2.Aconcenlrated(19.1mol/L)sodiumhydroxidesolution(alsoknownascausticsoda)whendilutedhaswide
spread use as a cleaner and disinfectant'
jar cleaner used by a commercial firm if 10.L of concenwhat is the molar concentration of a bottle and
400'L?
trated caustic soda solution is diluted to
s
3
Concentratedammonia(NH.13q;)solutionispreparedbydissolvingammoniagasinwater.Themolarcon.
14'8 mol/L
centration ol concentrated ammonta is
ol
(cautionl is required by a consumer to prepare 5'0 L
whar volume of concentrated aqueous ammonia
0.70 mol/L household ammonia?
4
Pure C, Hs OH , ethanol ', is 17.2
many cleaners.
and in
mollL. ln diluted lorm ethanol is present in all alcoholic beverages
pure ethanol De diluted in order to prepa re
To what volume must 10.0 mL of
1
0
.3 mol/ L
ethanol
type-cleaning solution?
01
14
c
Remedial
SOLUTIONS
DILUTION PROBLEMS
121
Remedial Problems
1' Household ammonia solution (0.70 mol/L) may be diluted to prepare a goll club cleaning solution (0.14
mol/L) or a comb and halrbrush cleaning sotution (0.021 mol/L).
What volume of household ammonia is required lo prepare 250,mL of
solution?
a comb and hairbrush cleaning
2. It
60.0 L of a 2.50 mol/L toxlc substance wer6 poured into a pond to glve a final volume at 5.00 x 103 L,
what would be the flnal concentration?
I
3'
To what llnalvolume must tho 60.0 L ol 2.50
final concentration 1.00 x
mol/L soluilon ln the prevlous probtem be diluted to make the
concentratlon for most toxic substances)?
10* mol/L. (a fairlv sale
4. Commercial concentration sulfuric acid is 17.6 mol/L. lf 1.50 L of 2.00 mol I L Hz SOn
(aq) is required in a
laboratory, how many millilitres of concentrated sulfuric acid
may be used? (when preparirig acid solutions
concentrated acid must be added to the water not vice versa).
e. f