After addition of the solid, the solution temperature is 27.0 degree C. The substances is known to have a molar mass of about 56 g/mol.
Calculate the enthalpy of solution in KJ/mol.
0.9775 grams of an unknow compound is dissolved in 50.0 mL of water. Initially, the water temperature is 22.3degree C.?
2019-03-06 12:55 am
回答 (1)
2019-03-06 1:32 am
Heat lost in dissolving the compound
= Heat gained by the water
= m c ΔT
= (50.0 g) × (4.184 J/g°C) × (27.0 - 22.3)°C
= 983.2 J
= 0.9832 kJ
Number of moles of the compound dissolve
= (0.9775 g) / (56 g/mol)
= 0.01746 mol
As heat is lost in dissolving the compound, the process is exothermic and ΔH(sol'n) < 0
Enthalpy of solution = -(0.9832 kJ) / (0.01746 mol) = -56.3 kJ/mol
= Heat gained by the water
= m c ΔT
= (50.0 g) × (4.184 J/g°C) × (27.0 - 22.3)°C
= 983.2 J
= 0.9832 kJ
Number of moles of the compound dissolve
= (0.9775 g) / (56 g/mol)
= 0.01746 mol
As heat is lost in dissolving the compound, the process is exothermic and ΔH(sol'n) < 0
Enthalpy of solution = -(0.9832 kJ) / (0.01746 mol) = -56.3 kJ/mol
收錄日期: 2021-05-01 22:28:37
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