Chemistry Reference
In-Depth Information
The volume of 0.5000 M
HNO
3
required is therefore
1 mL HNO
3
0.5000 mmol HNO
3
13.39
1
mmol HNO
3
a
b
26.78 mL HNO
3
Practice Problem 11.11
What volume of 0.1212 M
Ba(OH)
2
is
required to react with 41.74 mL of 0.2500 M HNO
3
?
EXAMPLE 11.12
Calculate the number of moles of NaCl produced by reaction of 0.0452 L of
4.20 M HCl and 0.120 L of 2.17 M NaOH.
Solution
Liters
of acid
Liters
of base
Because the quantities of two reactants are given, this problem involves a lim-
iting quantity.
a
4.20 mol HCl
1 L HCl
M
olari
ty
o
f aci
d
M
olar
ity
o
f bas
e
0.0452 L HCl
b
0.189
8
mol HCl
a
2.17 mol NaOH
1 L NaOH
0.120 L NaOH
b
0.260
4
mol NaOH
Moles
of acid
Moles
of base
NaOH(aq)
HCl(aq) £ NaCl(aq)
H
2
O(
/
)
Because the reactants react in a 1:1 mole ratio, NaOH is in excess, HCl is in
limiting quantity, and 0.190 mol of NaCl will be produced.
Balanced c
hemi
cal equation
Practice Problem 11.12
Calculate the number of milligrams of
NaCl that can be produced by the reaction of 22.4 mL of 2.00 M HCl and 1.74
g of NaOH.
Moles of
limiting quantity
Balanced ch
emic
al equation,
using lim
iting
quantity
The maximum molarity possible in an aqueous solution of an ionic com-
pound is about 40 M (with as the solute). Pure water itself contains
55.6 mol/L. Sometimes, knowing the maximum molarity is important for deter-
mining whether a calculated answer is reasonable, or for other purposes.
LiClO
3
Moles
of salt
EXAMPLE 11.13
Two ionic solutes, called A and B, are dissolved in the same solvent. The ratio of
the molarity of A to the molarity of B is
10
5
.
What can be deduced from this fact?
Solution
Chemists customarily represent the concentration of a substance by enclosing
its formula or symbol in square brackets. For example, [A] represents the molar-
ity of A. Then
[A]
[B]
10
5
1
