Yes, except transfer of heat into the water and not out of the rod and also only two sigfigs. Your turn!
- Answer
Yes, except transfer of heat into the water and not out of the rod and also only two sigfigs. Your turn!
- Answer
You fill a container with 3.5 L of water at an initial temperature of 90 °C. After 1 hour of cooling, you measure the temperature the temperature of the water to have dropped to 65 °C. Lastly, the surrounding temperature of the container remained at a steady 24 °C throughout the entire cooling process. Calculate the change in entropy for the entire system (including both the water and the surroundings).Yes, except transfer of heat into the water and not out of the rod and also only two sigfigs. Your turn!
You fill a container with 3.5 L of water at an initial temperature of 90 °C. After 1 hour of cooling, you measure the temperature the temperature of the water to have dropped to 65 °C. Lastly, the surrounding temperature of the container remained at a steady 24 °C throughout the entire cooling process. Calculate the change in entropy for the entire system (including both the water and the surroundings).Yes, except transfer of heat into the water and not out of the rod and also only two sigfigs. Your turn!
Hmm I got 187 J/K as my answer when I did it. I think the fourth line should beP.S. is there a better way to format the equations than having a separate tag ---- every line?
- Answer
Yeah, that's my bad.Hmm I got 187 J/K as my answer when I did it. I think the fourth line should be
with a minus instead of a plus. If it were plus, then you would see your temperature increasing (since Q is always positive) instead of decreasing. I redid your work with this correction and I got the same answer. What do you think?
Yeah, that's my bad.Hmm I got 187 J/K as my answer when I did it. I think the fourth line should be
with a minus instead of a plus. If it were plus, then you would see your temperature increasing (since Q is always positive) instead of decreasing. I redid your work with this correction and I got the same answer. What do you think?EDIT: Oh yeah, next question. An 10g iron rod at 50 degrees Celsius is dropped into a 1L beaker of water at 60 degrees Celsius. How does the length of the rod change? Use the values of c = 0.50 J/(g*K) for iron and c = 4.0 J/(g*K) for water. Use as many sigfigs as you want.
- Revised Answer
Alright this question has two parts. The chemical compound ethanol has an enthalpy of combustion of -1360 kJ/mol. You have a piston that can expand and contract. Assume that the lid of the piston is massless and the gas has a pressure of 1 atm. There are 5.2 moles of ideal gas in the piston at 730 K, and you apply enough heat such that the gas expands isothermally until its pressure is only 60% of the original pressure.Correct (as far as I know). Your turn!
Alright this question has two parts. The chemical compound ethanol has an enthalpy of combustion of -1360 kJ/mol. You have a piston that can expand and contract. Assume that the lid of the piston is massless and the gas has a pressure of 1 atm. There are 5.2 moles of ideal gas in the piston at 730 K, and you apply enough heat such that the gas expands isothermally until its pressure is only 60% of the original pressure.
1. How much work was done by the gas?
2. Assuming that the heat was added to the gas during this process was formed from the combustion of ethanol, find the number of moles of ethanol used in the reaction.
Yup that answer is correct! Also, I agree that there should be a specific tag for question marathons. Your turn!P.S. Is it just me or should we have an tag?
- Answer
What is the heat capacity of 50 kg of at 0 K? What is the heat capacity of 50 kg of at 273.15 K?
What is the heat capacity of 50 kg of at 0 K? What is the heat capacity of 50 kg of at 273.15 K?
- Answer?
I guess I still have a bit of studying to doWhat is the heat capacity of 50 kg of at 0 K? What is the heat capacity of 50 kg of at 273.15 K?
- Answer?
You can go though
- Not quite...
I guess I still have a bit of studying to do
- Answer?
You can go though
- Not quite...
You have a room with dimensions 4 meter by 13 meters by 9 meters. The room is filled with 46 kg of an ideal gas which is at a temperature of 22 °C. After pumping out some air, you find that the pressure of the room dropped by half and the temperature of the room dropped by 13 °C.
Find the mass of the air pumped out of the room.
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