16.34 g of CuSO4 dissolved in water giving out 55.51 kJ and 25.17 g CuSO4•5H2O absorbs 95.31 kJ. From the following reaction cycle and the experimental data above, calculate the enthalpy of hydration of CuSO4.

Respuesta :

Answer:

The enthalpy of hydration of copper sulphate is -1486.62 kJ/mol which means 1486.62kJ of energy is absorbed by one mole of copper sulphate during the process of hydration

Explanation:

Step 1: Determine the energy released per mole of [tex]CuSO_{4}[/tex] dissolved

[tex]{CuSO_{4}}_{(s)} -> {CuSO_{4}}_{(aq)}[/tex] (Eq. 1)

[tex]n_{CuSO_{4}} = \frac{m_{CuSO_{4}}}{M_{CuSO_{4}}} [/tex]

[tex]n_{CuSO_{4}} = \frac{16.34}{159.5} [/tex]

[tex]n_{CuSO_{4}} = 0.102 mol [/tex]

If 0.102 moles of [tex]CuSO_{4}[/tex] releases 55.51kJ of energy, 1 mole will release 541.85kJ/mol

[tex]{CuSO_{4}}_{(s)} -> {CuSO_{4}}_{(aq)}[/tex] ΔH = -541.85kJ/mol

Step 2: Determine the energy released per mole of [tex]CuSO_{4}.5H_{2}O[/tex] dissolved

[tex]{CuSO_{4}.5H_{2}O}_{(s)} -> {CuSO_{4}}_{(aq)}+{5H_{2}O}_{(l)}[/tex] (Eq. 2)

[tex]n_{CuSO_{4}.5H_{2}O} = \frac{m_{CuSO_{4}.5H_{2}O}}{M_{CuSO_{4}.5H_{2}O}} [/tex]

[tex]n_{CuSO_{4}.5H_{2}O} = \frac{25.17}{249.5} [/tex]

[tex]n_{CuSO_{4}.5H_{2}O} = 0.101 mol [/tex]

If 0.101 moles of [tex]CuSO_{4}.5H_{2}O[/tex] absorbs 95.31kJ of energy, 1 mole will absorb 944.77kJ/mol

[tex]{CuSO_{4}.5H_{2}O}_{(s)} -> {CuSO_{4}}_{(aq)}+{5H_{2}O}_{(l)}[/tex] ΔH = 944.77kJ/mol

Step 3: Subtracting Eq. 2 from Eq. 1

[tex]{CuSO_{4}}_{(s)} -> {CuSO_{4}}_{(aq)}[/tex] ΔH = -541.85kJ/mol (Eq. 1)

[tex]{CuSO_{4}.5H_{2}O}_{(s)} -> {CuSO_{4}}_{(aq)}+{5H_{2}O}_{(l)}[/tex] ΔH = 944.77kJ/mol (Eq. 2)

[tex]{CuSO_{4}}_{(s)} -{CuSO_{4}.5H_{2}O}_{(s)} -> {CuSO_{4}}_{(aq)} -{CuSO_{4}}_{(aq)}-{5H_{2}O}_{(l)}[/tex] ΔH = -541.85-944.77

[tex]{CuSO_{4}}_{(s)}+{5H_{2}O}_{(l)} -> {CuSO_{4}.5H_{2}O}_{(s)} [/tex] ΔH = -1486.62 kJ/mol

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