Question

The gas inside a cylinder expands against a constant external
pressure of **0.943** atm from a volume of
**3.35** L to a volume of **14.40** L. In
doing so, it turns a paddle immersed in **0.951** L of
liquid octane (**C _{8}H_{18}**).
Calculate the temperature rise of the liquid, assuming no loss of
heat to the surroundings or frictional losses in the mechanism.
Take the density of liquid

Hints: The expansion work done by the gas is given by: w = -P

delta T = ________°C

Answer #1

P_{ext} = 0.943 atm

Change in Volume = V_{2} - V_{1} = 14.40 - 3.35
= 11.05 L

thus, W = - p_{ext} * change in Volume = -0.943 atm *
11.05 L

= -10.42 L.atm * 101.325 J/L.atm = -1055.8J

Since no heat is lost

Thus, w = -q = -1055.8J

q = 1055.8J

Volume of octane = 0.951 L = 951 cm^{3}

density of octane = 0.703 g/cm^{3}

Mass of octane = Volume *density = 951
cm^{3} * 0.703 g/cm^{3} = 668.553 g

specific heat = **2.22** J °C-1 g-1.

Now, q = m*specific heat * delta T

1055.8J = 668.553 g* **2.22** J °C-1 g-1.* delta
T

**delta T = 0.711 ^{o}C**

A cylinder with a moving piston expands from an initial volume
of 0.250 L against an external pressure of 1.00 atm . The expansion
does 277 J of work on the surroundings. What is the final volume of
the cylinder?

A system expands from a volume of 1.00 L to 2.00 L against a
constant external pressure of 1.00 atm. What is the work (w) done
by the system? (1 L·atm = 101.3 J)

A 25.0-L sample of gas is compressed by a constant pressure of
1.267*10^5 Pa. If 328 J of work was done on the gas. what will be
the final volume of the gas? (1 L atm= 101.325 J)

A gas is compressed at a constant pressure of 0.800 atm from
10.00 L to 3.00 L. In the process, 400 J of energy leaves the gas
by heat.
(a)
What is the work done on the gas?
J
(b)
What is the change in its internal energy?
J

150 grams of C2H6 an ideal gas has an
initial pressure of 9120 mmHg and a temperature of 300 K. At a
constant temperature and moles, the gas changes to a final pressure
is 2280 mmHg.
a) Calculate the initial and final volumes (L)
b) Calculate the work done (in kJ) for the gas volume change if
it is carried out against a constant external pressure of 6 atm. (1
L atm = 101.325 J)
c) Using answer 5b, is...

A gas is confined to a cylinder under constant atmospheric
pressure, as illustrated in the following figure. When 0.470 kJ of
heat is added to the gas, it expands and does 219 J of work on the
surroundings.
1. What is the value of ΔH for this process?Express the energy
in kilojoules to three significant digits.
2. What is the value of ΔE for this process? Express the energy
in kilojoules to three decimal places.

1)A gas is allowed to expand, at constant temperature, from a
volume of 1.0 L to 10.1 L against an external pressure of 0.50 atm.
If the gas absorbs 250 J of heat from the surroundings, what is the
change in energy of the gas in J?
2)What is the energy in joules of one photon of microwave
radiation with a wavelength 0.122 m? (c = 2.9979 108
m/s; h = 6.626 10–34 Js)
3) What element is reduced in...

The gas is first cooled at constant volume until it reaches its
final pressure. It is then allowed to expand at constant pressure
until it reaches its final volume. (Use the following as necessary:
P1 = 2.90 atm, V1 = 0.90 L,
and Eint 1 = 451 J and its final state
P2 = 2.10 atm, V2 = 2.90 L,
and Eint 2 = 910 J.)
(a) Illustrate this process on a PV diagram (Do this on
paper. Your instructor...

A cylinder contains 250 g of Helium at 200 K. The external
pressure is constant at 1 atm. The temperature of the gas inside
the cylinder is then lowered by 85 K. Calculate q for this system
in response to the change made. Include units of J when entering
your answer.
Heat capacity for Helium = 20.8 J/(mol K) Molecular weight for
Helium = 4 g/mol
I tried doing the q=Cp*m*dT and got 110500 J but it was
incorrect.

32) 3.00 moles of an ideal gas are expanded isothermally
against a constant pressure of 1 atm from 2.0 liters to 10.0 liters
at a temperature of 20.0 C.
Which of the following is incorrect?
1. w = -PDV = -(1atm)(8 l) = -(101.3 J/l)(8 l) = -811.2 J
2. q = -w (since DU = 0) = 811.2 J
3. DU = 0 (since isothermal ideal gas)
4. DSSYS = ∆H/T = 0
33) In general, for a thermodynamic...

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 13 minutes ago

asked 14 minutes ago

asked 19 minutes ago

asked 28 minutes ago

asked 59 minutes ago

asked 59 minutes ago

asked 1 hour ago

asked 1 hour ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago