Answer:
a) 210 mL of 95% ethanol
b) 75 mL of water
Explanation:
a) We can use the dilution equation to solve this problem. C₁ and V₁ are the concentration and volume of the stock solution, respectively, while C₂ and V₂ are the concentration and volume of the diluted solution.
C₁V₁ = C₂V₂
We want to find V₁, the volume of ethanol stock we need to dilute to prepare the final solution:
V₁ = (C₂V₂) / C₁
The concentrations are represented in percentages. We substitute in the known values to calculate V₁. The units cancel to leave us with units of mL.
V₁ = (C₂V₂) / C₁ = (70%)(285mL) / (95%) = 210 mL
b) The final solution volume is 285 mL and we have added 210 mL of ethanol, so the remaining volume is from the water that we add:
(285 mL - 210 mL) = 75 mL
Answer:
In water PH+Poh=14. Ph=14-pOH=14-5=9
Explanation:sorry its so long hope this helps
O
H
=
−
log
10
[
H
O
−
]
by definition.
Thus
p
O
H
=
−
log
10
(
1
×
10
−
5
)
=
−
(
−
5
)
=
5
p
H
+
p
O
H
=
14
p
H
=
14
−
p
O
H
=
14
−
5
=
9
When we write
log
a
b
=
c
, we ask to what power we raise the base,
a
, to get
b
; here
a
c
=
b
. The normal bases are
10
,
(common logarithms)
, and
e
,
(natural logarithms)
.
Thus when we write
log
10
(
10
−
5
)
, we are asking to what power we raise
10
to get
10
−
5
. Now clearly the answer is
−
5
, i.e.
log
10
(
10
−
5
)
=
−
5
, alternatively
log
10
(
10
5
)
=
+
5
.
What are
log
10
(
100
)
,
log
10
(
1000
)
,
log
10
(
1000000
)
?
?
You shouldn't need a calculator, but use one if you don't see it straight off.
.2 moles of Carbon Dioxide because you are given .38 moles of water and you convert moles of water to grams and then into moles of CO2
Answer: Internal energy is the total kinetic energy and potential energy of all the particles (atoms and molecules) that make up a system.
Explanation:
Internal energy is the total kinetic energy and potential energy of all the particles (atoms and molecules) that make up a system. If a change of state happen, the energy needed for a substance to change state is called latent heat.
Hope this helps :)