The internal energy of an ideal gas depends only on its temperature. Do a first-law analysis of this process. A sample of an ideal gas is allowed to expand at constant temperature against atmospheric pressure.

Check Explanation

Explanation:

The Mathematical expression of the first law is given as

ΔU = Q - W

Note that depending on convention, the mathematical expression for the first law can be written as

ΔU = Q + W

a) Yes, the gas does work on its surroundings. Since it expands; indicating that there is a change in volume.

The work done is given as -PΔV if we are using the convention of (ΔU = Q + W). And this work is negative work done, since the system expands and does work on the surroundings.

But if we are using the convention of (ΔU = Q - W), the work done is given as PΔV and the workdone by the system on the environment is positive work during expansion.

b) Since this all takes place at constant temperature and against a constant atmospheric pressure, the change in internal energy for this system is 0. Change in internal energy depends on a change in temperature.

So, from the mathematical expression,

ΔU = Q + W or ΔU = Q - W

If ΔU = 0,

Q = - W or Q = W

But either ways,

Q = PΔV

(because, W = -PΔV for ΔU=Q+W and W = PΔV for ΔU=Q-W)

So, either ways, the heat transfer is the same and it is positive. This indicates heat is transferred from the surroundings to the system.

(c) What is ΔU for the gas for this process?

Since this all takes place at constant temperature and against a constant atmospheric pressure, the change in internal energy for this system is 0. Change in internal energy depends on a change in temperature.

Hope this Helps!!!

  the   balanced   equation   for   reaction of   ca metal   with   o2 to   produce   cao   is as below

2 ca+ o2→ 2 cao2

  explanation

the reaction is   balanced     since the   number of atoms   in reactant side is   equal to   number of atoms   in   product side.   for   example   they   are 2   atom of   ca in   reactant   side   and   2   atoms of ca   in   the product side.

  the   process   is a   meet the   requirement   of   redox   reaction because :     calcium   is   oxidized   from   oxidation state 0   to 2+   while   oxygen   is reduced from   oxidation   state   0   to 2-

under a microscope, cancer cells may look very different from normal cells. they often have different sizes and some may be larger than normal while others are smaller. cancer cells are often abnormally shaped and the control centre of the cell (the nucleus) may have an abnormal appearance.

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