How do you calculate the entropy change in the surroundings when 1.00 mol #N_2O_4(g)# is formed from #NO_2(g)# under standard conditions at 298 K?
[-192 #J K^-1# ]
[-192
From Levine's Physical Chemistry, my textbook:
By signing up, you agree to our Terms of Service and Privacy Policy
The entropy change in the surroundings can be calculated using the equation:
ΔS_surr = -ΔH_sys / T
Where: ΔS_surr = entropy change in the surroundings ΔH_sys = enthalpy change of the system T = temperature in Kelvin
First, you need to determine the enthalpy change of the system (ΔH_sys) for the reaction:
2NO2(g) -> N2O4(g)
Using standard enthalpies of formation: ΔH_sys = ΣΔHf(products) - ΣΔHf(reactants)
ΔH_sys = [0 kJ/mol - (-19.6 kJ/mol)] - [2(33.2 kJ/mol)]
ΔH_sys = -85.2 kJ/mol
Substitute ΔH_sys and the temperature (298 K) into the equation to find ΔS_surr.
By signing up, you agree to our Terms of Service and Privacy Policy
When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.
When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.
When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.
When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.
- #"6345 J"# of energy are required to raise the temperature of water from #22.6^@"C"# to #45.1^@"C"#. What is the mass of the water?
- If a sealed syringe that contains some gas is heated, in which direction will the syringe plunger move?
- A calorimeter contains 15 grams of water. The water's temperature increases by 10 C°. How much heat energy was added to the water? (Hint: water's specific heat is 1 cal/g°C)?
- Determine the specific heat of unknown metal from the fact that 6.40 * 10-2kj are needed to raise the temperature of 15g of unknown metal from 22 degrees Celsius to 33 degrees Celsius?
- How would you calculate the standard enthalpy change for the following reaction at 25 °C: H2O (g) + C (graphite)(s) --> H2 (g) + CO (g)?

- 98% accuracy study help
- Covers math, physics, chemistry, biology, and more
- Step-by-step, in-depth guides
- Readily available 24/7