All categories

3 years ago

A system does 125 J of work and cools down by releasing 438 J of heat. The change in internal energy is ____________ J.

Chemistry

1 answer:

Jet001 [13]3 years ago

8 0

Given that,

Work done by the system = 125 J

Energy released when it cools down = 438 J

To find,

The change in internal energy.

Solution,

As heat is released by the system, Q = -438 J

Work done by the system, W = -125 J

Using the first law of thermodynamics. The change in internal energy is given by :

$\Delta U=Q-W\\\\=-438-125\\\\=-563\ J$

So, the change in internal energy is 563 J.

You might be interested in

Carbon obtained from a sample of frozen skin in a glacier is found to have one-half the 14c-to-12c ratio of present-day carbon.

Otrada [13]

Check the attached file for the answer.

8 0

3 years ago

Wind power is:

12345 [234]

Answer) All of the above

7 0

3 years ago

Read 2 more answers

For the Zn - Cu^2+ voltaic cell Zn(s) + Cu^2+(aq, 1M) + Cu(s) E degree _cell = 1.10 V Given that the standard reduction potentia

Fittoniya [83]

Answer : The value of $E^o_{(Cu^{2+}/Cu)}$ is, 0.34 V

Explanation :

Here, copper will undergo reduction reaction will get reduced. Zinc will undergo oxidation reaction and will get oxidized.

The oxidation-reduction half cell reaction will be,

Oxidation half reaction: $Zn\rightarrow Zn^{2+}+2e^-$

Reduction half reaction: $Cu^{2+}+2e^-\rightarrow Cu$

Oxidation reaction occurs at anode and reduction reaction occurs at cathode. That means, gold shows reduction and occurs at cathode and chromium shows oxidation and occurs at anode.

The overall balanced equation of the cell is,

$Zn+Cu^{2+}\rightarrow Zn^{2+}+Cu$

To calculate the $E^o_{(Cu^{2+}/Cu)}$ of the reaction, we use the equation:

$E^o_{cell}=E^o_{cathode}-E^o_{anode}$

$E^o_{cell}=E^o_{(Cu^{2+}/Cu)}-E^o_{(Zn^{2+}/Zn)}$

Putting values in above equation, we get:

$1.10V=E^o_{(Cu^{2+}/Cu)}-(-0.76V)$

$E^o_{(Cu^{2+}/Cu)}=0.34V$

Hence, the value of $E^o_{(Cu^{2+}/Cu)}$ is, 0.34 V

8 0

3 years ago

Write a net ionic equation to show how codeine, c18h21o3n, behaves as a base in water.

Lera25 [3.4K]

Actually, the ionic equation for this is a reversible equation since codeine is a weak base. Any weak base or weak acids do not completely dissociate which makes them a reversible process. The ionic equation for this case is:

<span>C18H21O3N + H3O+ </span><=> C18H21O3NH+ + H2O

7 0

3 years ago

What dog is most like a wolf?

nekit [7.7K]

Answer:

Siberian Husky

Explanation:

7 0

3 years ago

Read 2 more answers