Calculate the heat that must be supplied to 10.5 g of Ne(g) at 0.15 atm to raise its temperature from 24◦C to 54◦C at constant pressure.
Assume that neon behaves as an ideal gas. Answer in units of J.
[So, I know that we would use q = mCDT at some point but because we're missing the specific heat capacity, we can't do that. How can we use pressure as a element in solving this problem? Perhaps there's equation that I'm not recalling. Thanks!]
For an ideal monatomic gas, Cp is (5/2)R. You can read about it here. In fact, several links you can get by Googling "heat capacity ideal gas" explains this better, I think, than the one I'm giving you.
http://hyperphysics.phy-astr.gsu.edu/hbase/kinetic/shegas.html
I hope you saw my correction for the bath tub of water. I picked up the dH for H2O2 and not H2O. My eye sight isn't that good anymore and those little subscripts are difficult for me to see. At any rate, I think the big problem you had with that was correcting J to kJ in the last step. But the 890 kJ/mol for the heat of combustion was correct and not that 694 something I wrote.
Alright, thank you. I'l let you know if I run into any more issues. And yes, I did see the correction.
To calculate the heat that must be supplied to 10.5 g of Ne(g) at constant pressure, we can use the equation:
q = nCpΔT
Where:
- q is the heat (energy) required,
- n is the number of moles of Ne(g),
- Cp is the molar heat capacity at constant pressure,
- ΔT is the change in temperature.
To calculate the number of moles, we can use the ideal gas law equation:
PV = nRT
Where:
- P is the pressure (0.15 atm),
- V is the volume (unknown but not needed for this problem),
- n is the number of moles,
- R is the ideal gas constant (0.0821 L·atm/(mol·K)),
- T is the temperature in Kelvin.
Rearranging this equation, we have:
n = PV / RT
Now let's calculate the number of moles:
n = (0.15 atm) * (V unknown) / (0.0821 L·atm/(mol·K)) * (273.15 + 24 °C)
As the volume is unknown, we can assume the gas is in a container at a constant volume or use any given volume if provided in the question.
Once we have the number of moles, we can calculate the heat by substituting the values into the equation mentioned earlier:
q = nCpΔT
We need to find the molar heat capacity at constant pressure (Cp) for neon (Ne). The molar heat capacity for an ideal gas at constant pressure is often given as 5/2 R, where R is the ideal gas constant (8.314 J/(mol·K)).
Therefore:
Cp = (5/2) R = (5/2) * 8.314 J/(mol·K)
Finally, substitute the values into the formula to calculate the heat:
q = nCpΔT