When a fixed amount of ideal gas goes through an isobaric expansion a) its internal (thermal) energy does not change. b) the gas does no work. c) no heat enters or leaves the gas. d) its temperature must increase. e) its pressure must increase.

Explanation:

In an isobaric process the pressure remains constant, which means the initial pressure and the final pressure will be the same.

In addition, during this thermodynamic process, the volume of the ideal gas expands or contracts in such a way that the variation of pressure is neutralized.

Now, according to the First law of Thermodynamics that establishes the conservation of energy:

  (1)

Where:

is the internal energy

is the heat transferred

is the work

Now, for an isobaric process:

   (2)

Where:

is the pressure (always positive)

is the volume variation of the gas

Here we have two possible results:

-If the gas expands (positive ), the work is positive.

-If the gas compresses (negative ), the work is negative.

In this case we are talking about the first result (work is positive).

Then, according to the above, equation (1) can be written as follows:

  (3)

Clearing :

   (4)

Then, for an ideal gas in an isobaric process, part of the heat () added to the system will be used to do work (positive in this case) and the other part will increase the internal energy, hence the temperature will increase as well.

  1.the balanced   chemical equation is as below

cu +   2 ag(no)₃ → cu(no₃)₂   +2 ag

2.the   much silver   produced   is   50.9 g

step 1: find the   moles of cu

moles =   mass÷   molar mass

  from periodic table the molar mass of cu = 63.5 g/mol

moles is therefore = 15.00 g÷ 63.5 g/mol = 0.236   moles

step 2: use the mole ratio to determine the   moles of ag

from equation above   cu: ag   is 1: 2

therefore the moles of ag   =0.236   moles   x 2/1 =0.472   moles

step 3: find the mass   of ag

mass = moles x molar mass

from periodic table   the molar mass of ag =107.87 g/mol

mass   = 0.472   moles x 107.87 g/mol = 50.9 g

3.   the   much   silver   collected worth is   1.797 oz

  convert   50.9 g   to oz

that is   1 gram = 0.0353 oz

          50.9 grams =?   oz

by cross multiplication

={(50.9 grams x 0.0353 oz) / 1   gram}   =1.797 oz

c) up

hope this