An ideal gas contained in a piston-cylinder assembly is compressed isothermally in an internally reversible process.
(a) determine if the entropy change of the gas is greater than, equal to or less than zero, justify your answer
(b) determine if for the same change of state, the entropy change for an irreversible process is greater than, equal to or less than part (a)

a)

b) entropy of the sistem equal to a), entropy of the universe grater than a).

Explanation:

a) The change of entropy for a reversible process:

The energy balance:

If the process is isothermical the U doesn't change:

The work:

If it is an ideal gas:

Solving:

Replacing:

Given that it's a compression: V2<V1 and ln(V2/V1)<0. So:

b) The entropy change of the sistem will be equal to the calculated in a), but the change of entropy of the universe will be 0 in a) (reversible process) and in b) has to be positive given that it is an irreversible process.

- "the choice that is not an indicator of a chemical change is "state of matter changes". more common than not, chemical reactions produce energy in the form of light or heat. along with energy, they also produce a new substance called the product that could be in any state of matter (solid, gas, or liquid)."

atomic number of carbon is 6

electronic configuration of carbon is 1s²2s²2p²

orbital diagram of carbon is as shown here in the image.