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5 moles of a liqiud L are converted into...

`5` moles of a liqiud `L` are converted into its vapour at its boiling point `( 273^(@)C)` and at a pressure of `1 "atm"`. If the value of latent heat of vapourisation of liquid `L` is `273 L atm//"mole"`, then which of the following statements is`//`are correct. Assume volume of liquid to be negligible and valpour of the liquid to behave ideally.

A

Work done by the system in the above process is `224 L` atm.

B

The enthalpy change `(Delta H)` for the above process is `1365 L` atm (with respect to magnitude only)

C

The internal energy of the system increases in the above process.

D

The value of `Delta U` for the above process is `1589 L` atm.

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To solve the problem step by step, we will analyze the process of converting 5 moles of liquid L into vapor at its boiling point and at a pressure of 1 atm. We will calculate the work done, enthalpy change, and internal energy change. ### Step 1: Calculate the Volume of Vapor Using the ideal gas law, we can calculate the volume of the vapor produced. The formula for volume \( V \) is given by: \[ V = nRT \] Where: - \( n = 5 \) moles - \( R = 0.0821 \, \text{L atm/(K mol)} \) (ideal gas constant) - \( T = 273 + 273 = 546 \, \text{K} \) (boiling point in Kelvin) Calculating the volume: \[ V = 5 \times 0.0821 \times 546 = 224.0 \, \text{L} \] ### Step 2: Calculate Work Done by the System The work done \( W \) by the system during the expansion can be calculated using the formula: \[ W = -P_{\text{external}} \Delta V \] Where: - \( P_{\text{external}} = 1 \, \text{atm} \) - \( \Delta V = V_{\text{final}} - V_{\text{initial}} = 224 \, \text{L} - 0 \, \text{L} = 224 \, \text{L} \) Calculating the work done: \[ W = -1 \times 224 = -224 \, \text{L atm} \] ### Step 3: Calculate Enthalpy Change (\( \Delta H \)) The enthalpy change can be calculated using the latent heat of vaporization: \[ \Delta H = n \times L \] Where: - \( L = 273 \, \text{L atm/mole} \) Calculating the enthalpy change: \[ \Delta H = 5 \times 273 = 1365 \, \text{L atm} \] ### Step 4: Calculate Change in Internal Energy (\( \Delta U \)) The change in internal energy can be calculated using the relation: \[ \Delta U = Q + W \] Where: - \( Q = \Delta H = 1365 \, \text{L atm} \) - \( W = -224 \, \text{L atm} \) Calculating the change in internal energy: \[ \Delta U = 1365 - 224 = 1141 \, \text{L atm} \] ### Summary of Results 1. Work done by the system: \( -224 \, \text{L atm} \) (correct statement) 2. Enthalpy change: \( 1365 \, \text{L atm} \) (correct statement) 3. Internal energy increases (correct statement) 4. Change in internal energy: \( 1141 \, \text{L atm} \) (incorrect statement) ### Conclusion The correct statements are: - Work done by the system is \( 224 \, \text{L atm} \) (correct). - Enthalpy change \( \Delta H \) is \( 1365 \, \text{L atm} \) (correct). - Internal energy of the system increases (correct). - The value of \( \Delta U \) is \( 1141 \, \text{L atm} \) (incorrect).

To solve the problem step by step, we will analyze the process of converting 5 moles of liquid L into vapor at its boiling point and at a pressure of 1 atm. We will calculate the work done, enthalpy change, and internal energy change. ### Step 1: Calculate the Volume of Vapor Using the ideal gas law, we can calculate the volume of the vapor produced. The formula for volume \( V \) is given by: \[ V = nRT \] ...
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