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The DeltaH(f)^(0)(KF,s) is -563 kJ mol^(...

The `DeltaH_(f)^(0)(KF,s)` is `-563 kJ mol^(-1)`. The ionization enthalpy of `K(g)` is `419 kJ mol^(-1)`. and the enthalpy of sublimation of potassium is `88 kJ mol^(-1)`. The electron affinity of `F(g)` is `322 kJ mol^(-1)` and `F-F` bond enthalpy is `158 kJ mol^(_1)`. Calculate the lattice enthalpy of `KF(s)`.
The given data are as follows:
(i) `K(s)+1//2F_(2)(g)rarrKF(s)" "DeltaH_(f)^(0)= -563 kJ mol^(-1)`
(ii) `K(g)rarrK^(+)(g)+e^(-)" "Delta_("Ioniz")^(0)=419 kJ mol^(-1)`
(iii) `K(s)rarrK(g)" "DeltaH_("sub")^(0)=88kJ mol^(-1)`
(iv) `F(g)+e^(-)rarrF^(-)(g)" "DeltaH_(eg)^(0)= -322 kJ mol^(-1)`
(v) `F_(2)(g)rarr2F(s)" "DeltaH_("diss")^(0)= 158 kJ mol^(-1)`
(vi) `K^(+)(g)+F^(-)(g)rarrKF(s)" " DeltaH_(L)^(0)=?`

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The correct Answer is:
To calculate the lattice enthalpy of KF(s), we will use Hess's law and the given thermodynamic data. We will manipulate the provided reactions to derive the lattice enthalpy. ### Step-by-Step Solution: 1. **Write down the given reactions and their enthalpy changes:** - (i) \( K(s) + \frac{1}{2} F_2(g) \rightarrow KF(s) \) \(\Delta H_f^{0} = -563 \, \text{kJ mol}^{-1}\) - (ii) \( K(g) \rightarrow K^+(g) + e^- \) \(\Delta H_{ionization}^{0} = 419 \, \text{kJ mol}^{-1}\) - (iii) \( K(s) \rightarrow K(g) \) \(\Delta H_{sub}^{0} = 88 \, \text{kJ mol}^{-1}\) - (iv) \( F(g) + e^- \rightarrow F^-(g) \) \(\Delta H_{eg}^{0} = -322 \, \text{kJ mol}^{-1}\) - (v) \( F_2(g) \rightarrow 2F(g) \) \(\Delta H_{diss}^{0} = 158 \, \text{kJ mol}^{-1}\) - (vi) \( K^+(g) + F^-(g) \rightarrow KF(s) \) \(\Delta H_L^{0} = ?\) 2. **Manipulate the reactions:** - Start with reaction (i) and rearrange it to find the lattice enthalpy: \[ \Delta H_L^{0} = \Delta H_f^{0} - \Delta H_{ionization}^{0} - \Delta H_{sub}^{0} - \Delta H_{eg}^{0} - \frac{1}{2} \Delta H_{diss}^{0} \] 3. **Substitute the values into the equation:** - Substitute the known values into the equation: \[ \Delta H_L^{0} = -563 - 419 - 88 + 322 - \frac{1}{2} \times 158 \] 4. **Calculate the values step-by-step:** - Calculate \( -563 - 419 = -982 \) - Calculate \( -982 - 88 = -1070 \) - Calculate \( -1070 + 322 = -748 \) - Calculate \( -\frac{1}{2} \times 158 = -79 \) - Finally, calculate \( -748 - 79 = -827 \) 5. **Final result:** - The lattice enthalpy of \( KF(s) \) is: \[ \Delta H_L^{0} = -827 \, \text{kJ mol}^{-1} \] ### Summary: The lattice enthalpy of KF(s) is \(-827 \, \text{kJ mol}^{-1}\).

To calculate the lattice enthalpy of KF(s), we will use Hess's law and the given thermodynamic data. We will manipulate the provided reactions to derive the lattice enthalpy. ### Step-by-Step Solution: 1. **Write down the given reactions and their enthalpy changes:** - (i) \( K(s) + \frac{1}{2} F_2(g) \rightarrow KF(s) \) \(\Delta H_f^{0} = -563 \, \text{kJ mol}^{-1}\) - (ii) \( K(g) \rightarrow K^+(g) + e^- \) ...
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