At 25°C, the standard enthalpy of formation of KCl(s) is –435.87 kJ/mol. When one mole of KCl(s) is formed by reacting potassium vapor and chlorine gas at 25°C, the standard enthalpy of reaction is –525.86 kJ/mol. Find ΔH° for the sublimation of potassium, K(s) → K(g), at 25°C(A) –345.88 kJ/mol(B) 45.00 kJ/mol(C) 345.88 kJ/mol(D) 89.99 kJ/mol(E) –525.86 kJ/mol

At 25°C, the standard enthalpy of formation of KCl(s) is –435.87 kJ

1.	At 25°C, the standard enthalpy of formation of KCl(s) is –435.87 kJ/mol. When one mole of KCl(s) is formed by reacting potassium vapor and chlorine gas at 25°C, the standard enthalpy of reaction is –525.86 kJ/mol. Find ΔH° for the sublimation of potassium, K(s) → K(g), at 25°C(A) –345.88 kJ/mol(B) 45.00 kJ/mol(C) 345.88 kJ/mol(D) 89.99 kJ/mol(E) –525.86 kJ/mol
Answer» (D) 89.99 kJ/mol

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