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Standard XII

Chemistry

Molar and Specific Heat Capacity

At 298 K, the...

Question

At 298 K, the heat of solution of MgSO $_{4}$ (s) is -91.21 KJ mol $^{- 1}$ and that of MgSO $_{4}$ . 7 H $_{2}$ O (s) is 13.81 KJ mol $^{- 1}$ . Calculate heat of hydration of MgSO $_{4}$ i.e., $Δ$ H for the reaction $M g S O_{4} (s) + 7 H_{2} O (l) \to M g S O_{4} .7 H_{2} O (s)$

-105.02 KJ mol

^{- 1}

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105.02 KJ mol

^{- 1}

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-77.40 KJ mol

^{- 1}

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77.40 KJ mol

^{- 1}

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Solution

The correct option is A -105.02 KJ mol $^{- 1}$
$M g S O_{4} (s) + 7 H_{2} O (l) \to M g S O_{4} .7 H_{2} O (s)$
$Δ H =$ Heat of solution of $M g S O_{4} (s)$ - Heat of solution of $M g S O_{4} (s) .7 H_{2} O (s)$
$= - 91.21 K J m o l^{- 1} - 13.81 K J$ $= - 105.02 K J m o l^{- 1}$

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At 298 K, the heat of solution of MgSO4 (s) is -91.21 KJ mol−1 and that of MgSO4. 7 H2O (s) is 13.81 KJ mol−1. Calculate heat of hydration of MgSO4 i.e., ΔH for the reaction MgSO4(s)+7H2O(l)→MgSO4.7H2O(s)

The correct option is A -105.02 KJ mol−1MgSO4(s)+7H2O(l)→MgSO4.7H2O(s)ΔH= Heat of solution of MgSO4(s) - Heat of solution of MgSO4(s).7H2O(s)=−91.21KJmol−1−13.81KJ =−105.02KJmol−1

At 298 K, the heat of solution of MgSO $_{4}$ (s) is -91.21 KJ mol $^{- 1}$ and that of MgSO $_{4}$ . 7 H $_{2}$ O (s) is 13.81 KJ mol $^{- 1}$ . Calculate heat of hydration of MgSO $_{4}$ i.e., $Δ$ H for the reaction $M g S O_{4} (s) + 7 H_{2} O (l) \to M g S O_{4} .7 H_{2} O (s)$

The correct option is A -105.02 KJ mol $^{- 1}$
$M g S O_{4} (s) + 7 H_{2} O (l) \to M g S O_{4} .7 H_{2} O (s)$
$Δ H =$ Heat of solution of $M g S O_{4} (s)$ - Heat of solution of $M g S O_{4} (s) .7 H_{2} O (s)$
$= - 91.21 K J m o l^{- 1} - 13.81 K J$ $= - 105.02 K J m o l^{- 1}$