Home
Class 12
CHEMISTRY
Considering the reaction, C(s) + O(2)(...

Considering the reaction,
`C(s) + O_(2)(g) to CO_(2)(g) + 393.5 kJ`
the signs of `DeltaH, DeltaS` and `DeltaG` respectively are:

A

`+,-,-`

B

`-,+,-`

C

`-,-,-`

D

`-,+,1`

Text Solution

AI Generated Solution

The correct Answer is:
To determine the signs of ΔH, ΔS, and ΔG for the reaction: \[ C(s) + O_2(g) \rightarrow CO_2(g) + 393.5 \, \text{kJ} \] we will analyze each thermodynamic quantity step by step. ### Step 1: Determine ΔH (Change in Enthalpy) 1. **Identify the type of reaction**: The given reaction is a combustion reaction, where carbon (solid) reacts with oxygen (gas) to form carbon dioxide (gas) and releases energy (393.5 kJ). 2. **Sign of ΔH**: In combustion reactions, energy is released, indicating that the reaction is exothermic. Therefore, the change in enthalpy (ΔH) is negative. \[ \Delta H < 0 \] ### Step 2: Determine ΔS (Change in Entropy) 1. **Analyze the states of matter**: In the reaction, we start with one solid (C) and one gas (O₂), and we end up with one gas (CO₂). 2. **Change in disorder**: The transition from solid and gas to only gas generally leads to an increase in disorder (entropy). However, since we are losing one mole of gas (O₂) while producing one mole of gas (CO₂), we need to consider the overall change. 3. **Sign of ΔS**: In this case, the reaction results in a decrease in the number of gas moles, which typically leads to a decrease in entropy. Therefore, ΔS is negative. \[ \Delta S < 0 \] ### Step 3: Determine ΔG (Change in Gibbs Free Energy) 1. **Use the Gibbs Free Energy equation**: The relationship between ΔG, ΔH, and ΔS is given by the equation: \[ \Delta G = \Delta H - T\Delta S \] 2. **Evaluate ΔG**: Since ΔH is negative and ΔS is also negative, the term \( -T\Delta S \) will be positive (as T is always positive). However, because ΔH is significantly negative due to the exothermic nature of the reaction, it will dominate the equation. 3. **Sign of ΔG**: Therefore, ΔG will also be negative, indicating that the reaction is spontaneous. \[ \Delta G < 0 \] ### Conclusion Based on the analysis: - ΔH is negative, - ΔS is negative, - ΔG is negative. Thus, the signs of ΔH, ΔS, and ΔG respectively are: \[ \text{Negative, Negative, Negative} \]

To determine the signs of ΔH, ΔS, and ΔG for the reaction: \[ C(s) + O_2(g) \rightarrow CO_2(g) + 393.5 \, \text{kJ} \] we will analyze each thermodynamic quantity step by step. ### Step 1: Determine ΔH (Change in Enthalpy) ...
Promotional Banner

Topper's Solved these Questions

  • THERMODYNAMICS

    VMC MODULES ENGLISH|Exercise LEVEL-2|50 Videos
  • THERMODYNAMICS

    VMC MODULES ENGLISH|Exercise LEVEL-2 (NUMERICAL VALUE TYPE)|15 Videos
  • THERMODYNAMICS

    VMC MODULES ENGLISH|Exercise LEVEL-0 (LONG ANSWER TYPE (5 MARKS))|6 Videos
  • THERMOCHEMISTRY

    VMC MODULES ENGLISH|Exercise JEE ADVANCED (ARCHIVE)|31 Videos
  • THERMODYNAMICS & THERMOCHEMISTRY

    VMC MODULES ENGLISH|Exercise Impeccable|48 Videos

Similar Questions

Explore conceptually related problems

Consider the reacton C(s) + (1)/(2) O_(2)(g) rarr CO(g) + 200 kJ The signs of Delta S, Delta H and Delta G respectively are

For the reaction 2H(g)rarr H_(2)(g) , the sign of DeltaH and DeltaS respectively are :

Consider the following spontaneous reaction 3X_(2)(g)rarr2X_(3)(g) . What are the sign of DeltaH , DeltaS and DeltaG for the reaction ?

Consider the following reaction. C_(6)H_(6)(l)+(15)/(2)O_(2)(g)rarr6CO_(2)(g)+3H_(2)O(g) signs of DeltaH, DeltaS and DeltaG for the above reaction will be

In the reaction, CO_(2)(g)+H_(2)(g)toCO(g)+H_(2)O(g)," "DeltaH=2.8 kJ DeltaH represents :

Consider the following reaction : CO_((g))+(1)/(2)O_(2(g)) rarr CO_(2(g)) How are Delta U and DeltaH related for the reaction ?

Statement -1 in the following reaction : C(s)+O_(2)(g)to CO_(2) (g), DeltaH=DeltaU-RT Statement -2: DeltaH Is related to DeltaU by the equation , DeltaH=DeltaU+Deltan_(g)RT

For the reaction C_(3)H_(8)(g) + 5 O_(2)(g) rightarrow 3CO_(2)(g) + 4 H_(2)O(l) at constant temperature , DeltaH - Delta E is

Fe_(2)O_(2)(s)+(3)/(2)C(s)to(3)/(2)CO_(2)(g)+2Fe(s) DeltaH^(@)=+234.12KJ C(s)+O_(2)(g)toCO_(2)(g) DeltaH^(@)=-393.5KJ Use these equations and DeltaH^(@) value to calculate DeltaH^(@) for this reaction : 4Fe(s)+3O_(2)(g)to2Fe_(2)O_(3)(s)

For the reaction, C+O_(2) rarr CO_(2),DeltaH=-393 J 2Zn + O_(2) rarr 2ZnO, DeltaH=-412 J

VMC MODULES ENGLISH-THERMODYNAMICS-LEVEL-1
  1. The enthalpy change for transition of liquid water to steam is 40.8 kJ...

    Text Solution

    |

  2. Which of the following statements is true?

    Text Solution

    |

  3. In a reversible process, the value of Delta S (sys) + Delta S(surr) is

    Text Solution

    |

  4. Consider the following cyclic process. I. Isothermal , II. Adiaba...

    Text Solution

    |

  5. The following diagram represents the (p-V) changes of gas. Thus, total...

    Text Solution

    |

  6. Which of the following proces is (are) expected to be spontaneous at h...

    Text Solution

    |

  7. Which of the plots of ln K vs (1/T) is/are correct?

    Text Solution

    |

  8. The value of DeltaH("transition") of C (graphite) rarr C (diamond) is ...

    Text Solution

    |

  9. Among the following , the state funcation (s) is (are)

    Text Solution

    |

  10. For an endothermic reaction, Delta H represents the enthalpy of the re...

    Text Solution

    |

  11. Match the following:

    Text Solution

    |

  12. Match the Column:

    Text Solution

    |

  13. For the gas phase reaction, PCl(5)(g) hArr PCl(3)(g) + Cl(2)(g) Wh...

    Text Solution

    |

  14. The Haber's process of production of ammonia involves the equilibrium:...

    Text Solution

    |

  15. If a gas, at constant temperature and pressure expands, then its

    Text Solution

    |

  16. Considering the reaction, C(s) + O(2)(g) to CO(2)(g) + 393.5 kJ th...

    Text Solution

    |

  17. Considering entropy (S) as a thermodynamic parameter, the criterion fo...

    Text Solution

    |

  18. Assuming DeltaH^(@) and S^(@) do not change with temperature. Calculat...

    Text Solution

    |

  19. For a phase change: H(2)O(l)hArrH(2)O(s) 0^(@)C, 1 bar

    Text Solution

    |

  20. For the process H(2)O(l) (1 "bar", 373 K) rarr H(2)O(g) (1"bar", 373 K...

    Text Solution

    |