Answer:
uy pasagot kung nasagutan mo na pls wala pa akong sagot jan
(a)
pH = 4.77
; (b)
[
H
3
O
+
]
=
1.00
×
10
-4
l
mol/dm
3
; (c)
[
A
-
]
=
0.16 mol⋅dm
-3
Explanation:
(a) pH of aspirin solution
Let's write the chemical equation as
m
m
m
m
m
m
m
m
l
HA
m
+
m
H
2
O
⇌
H
3
O
+
m
+
m
l
A
-
I/mol⋅dm
-3
:
m
m
0.05
m
m
m
m
m
m
m
m
l
0
m
m
m
m
m
l
l
0
C/mol⋅dm
-3
:
m
m
l
-
x
m
m
m
m
m
m
m
m
+
x
m
l
m
m
m
l
+
x
E/mol⋅dm
-3
:
m
0.05 -
l
x
m
m
m
m
m
m
m
l
x
m
m
x
m
m
m
x
K
a
=
[
H
3
O
+
]
[
A
-
]
[
HA
]
=
x
2
0.05 -
l
x
=
3.27
×
10
-4
Check for negligibility
0.05
3.27
×
10
-4
=
153
<
400
∴
x
is not less than 5 % of the initial concentration of
[
HA
]
.
We cannot ignore it in comparison with 0.05, so we must solve a quadratic.
Then
x
2
0.05
−
x
=
3.27
×
10
-4
x
2
=
3.27
×
10
-4
(
0.05
−
x
)
=
1.635
×
10
-5
−
3.27
×
10
-4
x
x
2
+
3.27
×
10
-4
x
−
1.635
×
10
-5
=
0
x
=
1.68
×
10
-5
[
H
3
O
+
]
=
x
l
mol/L
=
1.68
×
10
-5
l
mol/L
pH
=
-log
[
H
3
O
+
]
=
-log
(
1.68
×
10
-5
)
=
4.77
(b)
[
H
3
O
+
]
at pH 4
[
H
3
O
+
]
=
10
-pH
l
mol/L
=
1.00
×
10
-4
l
mol/L
(c) Concentration of
A
-
in the buffer
We can now use the Henderson-Hasselbalch equation to calculate the
[
A
-
]
.
pH
=
p
K
a
+
log
(
[
A
-
]
[
HA
]
)
4.00
=
−
log
(
3.27
×
10
-4
)
+
log
(
[
A
-
]
0.05
)
=
3.49
+
log
(
[
A
-
]
0.05
)
log
(
[
A
-
]
0.05
)
=
4.00 - 3.49
=
0.51
[
A
-
]
0.05
=
10
0.51
=
3.24
[
A
-
]
=
0.05
×
3.24
=
0.16
The concentration of
A
-
in the buffer is 0.16 mol/L.
hope this helps :)
Answer is:
7.8 lb of 21% aluminum and 33.2 ib of <span>
42% aluminum.</span>
ω₁<span> = 21% ÷ 100% = 0.21.
ω</span>₂<span> = 42% ÷ 100% = 0.42.
ω</span>₃<span> = 38% ÷ 100% = 0.38.
</span>m₁ = ?.
m₂<span> = ?.
</span>m₃ = m₁ + m₂<span>.
</span>m₃ = 41 pounds.
m₁ = 41 lb - m₂<span>.
ω</span>₁ · m₁ + ω₂ ·m₂ = ω₃ · m₃.
0.21 · (41 lb -
m₂) + 0.42 · m₂ = 0.38 · 41 lb.
8.61 lb - 0.21m₂ + 0.42m₂ = 15.58 lb.
0.21m₂ = 6.97 lb.
m₂ = 6.97 lb ÷ 0.21.
m₂ = 33.2 lb.
m₁ = 41 lb - 33.2 lb.
m₁<span> = 7.8 lb.</span>
Answer:
Electrolytes are defined as those compounds which dissolve in a solvent such as water to produce a solution which conducts electric current easily.
Explanation:
Electrolytes are chemical compounds that dissolve in a solvent such as water and dissociate into ions (cations and anions) which helps to conduct electric current. They can be solids, liquids, or solutions and examples include all ionic compounds such as sodium chloride, calcium chloride, etc.
When electrodes are placed in a solution containing an electrolyte, the ions produced in the solution move from one electrode to the other. The negatively charged ions called anions are attracted to the positive electrode and the positively charged ions called cations are attracted to the negative electrode. This movement of ions generates an electric current. Electrolytes are also needed for the various electrochemical processes in living things and the main ions in these electrolytes are sodium (Na+), calcium (Ca2+), potassium (K+), magnesium (Mg2+), chloride (Cl-), etc.
Answer:
To calculate the Carbon Dioxide - CO 2 - emission from a fuel, the carbon content of the fuel must be multiplied with the ratio of molecular weight of CO 2 (44) to the molecular weight of Carbon (12) -> 44 / 12 = 3.7 Emission of CO 2 from combustion of some common fuels are indicated in the table
Explanation: