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What is the molar mass of H2O
identify each layer and describe the three soil horizons and explain the formation and composition of each.
Calculate the Gibbs energy, entropy, and enthalpy of mixing when 1.00 mol C6H14 (hexane) is mixed with 1.00 mol C7H16 (heptane) at 298 K; treat the solution as ideal
The heat evolved from the combustion of 0.94g ethanol raises the temperature of
250 cm3 water contained in a copper beaker by 20.0 °C. [Specific heat capacity of
solution = 4.18 Jg-1 °C-1; density of solution = 1.0 g cm-3]
i) What is the enthalpy of combustion per mol of ethanol?
ii) Calculate the temperature rise when 1.50 g ethanol is used to heat 500 cm3
water in the same copper beaker.
Assume that you take a flask, evacuate it to remove all the air, and finds its mass to be 478.1 g. You then fill the flask with argon to a pressure of 2.15 atm and reweigh it. What would the balance read (in grams) if the flask has a volume of 7.35 L and the temperature is 20.0 oC?
The
Schrödinger equation
is a
linear
partial differential equation
t
hat governs the
wave function
of
a quantum
-
mechanical system. The most general form is the time
-
dependent Schrödinger equation,
which gives a description of a system evolving wi
th time and it
i
s given as follow:
i
ħ
𝑑
𝑑𝑡
ǀ
𝜓
(
𝑡
)
) =
𝐻
̂
ǀ
𝜓
(t))
As in
Schrödinger
’s cat illustration, c
onsider an electron as a
“
particle in a box
”
with
a kinetic
energy (KE) of 1
00
J
.
Based on the given information, c
alculate the uncertainty
in position (
∆
𝑥
)
for this electron
. State all your assumptions
(if any)
.
In the electrowinning process, a
Metallurgical/Chemical
Engineer
use
s
an Infrared (IR) camera to
detect metallurgical short
-
circuits (hot spots) over the anodes and cathodes.
Given that the mass
of an electron is 9.109
×
10
31
𝐾𝑔
and
Rydberg
’s
constant is
1.090×
10
7
𝑚
−
1
,
d
etermine the energy
(in MJ)
applied when
5
mol of IR photons having a wavelength of 3
2
nm is
used in the copper
electrolysis process
.
2483g sample of NaOH was dissolved in water to get 250ml of the solution. 18.8ml of 0.105N HCl solution were used for the titration of the 20ml of the prepared solution. Calculate the mass percentage of the alkali in sample.
How do I calculate delta E° of the equation Cl2 + 2Br2 = 2Cl. As well is it a spontaneous or non-spontaneous reaction at standard conditions?
A pre-filtered river water 10ml is added to a 100ml volumetric flask along with the 20ml of La+cs solution (to minimise matrix effects) and then ultrapure water is added to make up the mark.
A Ca²+ concentration of 2.3 meq/L is determined from the calibration curve .
What is the Ca²+ concentration in the original river water sample in meq/L and mg/L?
