What is the final temperature of the expanding monatomic gas?

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The discussion revolves around calculating the final temperature of an expanding monatomic ideal gas, starting with 5.00 moles at an initial temperature of 127°C. The gas absorbs 1220 J of heat and does 2180 J of work, leading to a change in internal energy (ΔU) of -960 J. Participants clarify that the heat absorbed (Q) is indeed the value provided, and the relationship Q = ΔU + W can be used to find the final temperature. To determine the final temperature, one must calculate the initial internal energy and adjust for the change. Understanding the distribution of internal energy in an ideal gas is crucial for solving the problem.
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We start with 5.00 moles of an ideal monatomic gas with an initial temperature of 127C. The gas expands and, in the process, absorbs an amount of heat equal to 1220 J and does an amount of work equal to 2180 J.

I fouind out the change in U, which is -960. I'm just not sure how to calculate Q. Any help would be greatly appreciated.
 
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~angel~ said:
We start with 5.00 moles of an ideal monatomic gas with an initial temperature of 127C. The gas expands and, in the process, absorbs an amount of heat equal to 1220 J and does an amount of work equal to 2180 J.

I fouind out the change in U, which is -960. I'm just not sure how to calculate Q. Any help would be greatly appreciated.

I don't understand the question. Why isn't Q the heat absorbed that you were given?
 
Sorry, I forgot to ask the question (I just copied and pasted it).

The question is:

What is the final temperature T_final of the gas?
Use R = 8.3145 J/mol/K for the ideal gas constant.
 
Use Q = \Delta U + W.
 
~angel~ said:
Sorry, I forgot to ask the question (I just copied and pasted it).

The question is:

What is the final temperature T_final of the gas?
Use R = 8.3145 J/mol/K for the ideal gas constant.

You should be able to calculate the initial internal energy of the gas, given that you know the termperature, how much gas you have, and that it is ideal monatomic. You know how much internal energy was lost in the process, so you know the final internal energy, from which you can calculate the final temperature. Look for the discussion in your text or notes about how internal energy in an ideal gas is distributed.
 
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