# Calculating Final Temperature of Hydrogen Gas

• J_B__
In summary: The entropy change in the Hydrogen gas can be calculated using the equation ΔS = n*Cp*ln(T2/T1), where n is the number of moles, Cp is the specific heat at constant pressure, and T1 and T2 are the initial and final temperatures. Plugging in the values given, we get ΔS = (1.5/2.01588)*29.1*ln(393.1/300) = 1.75 kJ/K. The entropy change of the overall process can be calculated using the equation ΔS = ΔQ/T, where ΔQ is the heat added to the system and T is the final temperature. Plugging in the values, we get ΔS =
J_B__
I need a little help getting this one started...

1.5 kg of Hydrogen gas at 8 bars and 27 degrees C are contained in a constant pressure piston-cylinder arrangement. Heat in the amount of 1740 kJ is added to the Hydrogen from a reservior at 400 degrees K. Determine: the final temperature of the Hydrogen Gas, the entropy change in the Hydrogen gas in kJ/degree K, the entropy change of the overall process (system and surroundings) in kJ/degree K, is the process reversible, irreversible, possible, or impossible?

(I think i can get the last three parts, but i cannot seem to figure out how to get the final temperature)

Thanks

!The final temperature of the Hydrogen gas can be calculated using the ideal gas law. The equation is PV = nRT, where P is the pressure, V is the volume, n is the number of moles of gas, R is the ideal gas constant, and T is the temperature. In this case, we know the pressure (8 bars), the volume (1.5 kg of Hydrogen), and the number of moles (n=1.5/2.01588). Rearranging the equation to solve for T, we get T = PV/(nR). Plugging in the values given, we get T = 8*1.5/[(1.5/2.01588)*8.314] = 393.1 K. Therefore, the final temperature of the Hydrogen gas is 393.1 K.

for reaching out for help with this problem! Calculating the final temperature of the hydrogen gas may seem daunting, but let's break it down step by step. First, we need to determine the initial state of the hydrogen gas. We know that it has a mass of 1.5 kg, a pressure of 8 bars, and a temperature of 27 degrees C. We can use the ideal gas law to calculate the initial volume of the hydrogen gas.

PV = nRT

Where P is pressure, V is volume, n is number of moles, R is the ideal gas constant (8.314 J/mol*K), and T is temperature.

We can rearrange this equation to solve for volume:

V = nRT/P

Since we know the mass of the hydrogen gas (1.5 kg) and its molar mass (2.016 g/mol), we can calculate the number of moles present:

n = m/M = (1.5 kg)/(2.016 g/mol) = 0.744 mol

Now we can plug in all of our values to solve for the initial volume:

V = (0.744 mol)(8.314 J/mol*K)(300 K)/(8 bar) = 232.9 L

Next, we need to use the first law of thermodynamics to calculate the final temperature of the hydrogen gas. The first law of thermodynamics states that the change in internal energy of a system is equal to the heat added to the system minus the work done by the system:

ΔU = Q - W

In this case, we are given the amount of heat added to the hydrogen gas (1740 kJ) and we know that the process is taking place at constant pressure, so the work done by the system is simply the pressure multiplied by the change in volume:

W = PΔV

We can calculate the change in volume by using the ideal gas law again, but this time we are solving for the change in volume:

ΔV = nRΔT/P

Since the initial and final pressures are the same, we can cancel them out:

W = PΔV = P(nRΔT/P) = nRΔT

Now we can plug in all of our values to solve for the change in internal energy:

ΔU = Q - W = 1740 kJ - (0.744 mol)(8.314 J/mol*K)(

## 1. How do you calculate the final temperature of hydrogen gas?

To calculate the final temperature of hydrogen gas, you can use the ideal gas law equation: PV = nRT. First, you will need to determine the initial pressure (P), volume (V), and number of moles (n) of the hydrogen gas. Then, plug these values into the equation along with the gas constant (R = 8.314 J/mol*K) and solve for the final temperature (T).

## 2. What units should be used for the values in the ideal gas law equation?

The ideal gas law equation requires the use of consistent units. Pressure (P) should be in units of Pascals (Pa), volume (V) in cubic meters (m^3), number of moles (n) in moles (mol), and temperature (T) in Kelvin (K).

## 3. Can the final temperature of hydrogen gas be negative?

Yes, the final temperature of hydrogen gas can be negative if the initial temperature and pressure are both low enough. This indicates that the gas has cooled down significantly and its molecules have slowed down enough to condense into a liquid or solid state.

## 4. What other factors can affect the final temperature of hydrogen gas?

The final temperature of hydrogen gas can also be affected by the specific heat capacity of the gas, any heat transfer to or from the surroundings, and any changes in the number of moles of gas (such as through a chemical reaction).

## 5. How accurate is the ideal gas law equation in calculating the final temperature of hydrogen gas?

The ideal gas law equation assumes that the gas molecules do not interact with each other and that their volume is negligible. This may not always be the case, especially at high pressures or low temperatures. Therefore, the accuracy of the equation may vary and it is important to consider any deviations from ideal behavior when using it to calculate the final temperature of hydrogen gas.

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