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1 year ago

Convert 3.9 kcal into calories.

Chemistry

1 answer:

timama [110]1 year ago

8 0

$3.9 ~\text{kcal} = 3.9 \times 1000 ~ \text{cal} = 3900~ \text{cal.}$

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2 years ago

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Answer:

The enthalpy of the reaction is coming out to be -380.16 kJ.

Explanation:

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The equation for the enthalpy change of the above reaction is:

$\Delta H_{rxn}=[(2 mol\times \Delta H_f_{(N_2O)})+(2 mol\times\Delta H_f_{(H_2O)} )]-[(1 mol\times \Delta H_f_{(N_2H_4)})+(1 mol\times \Delta H_f_{(N_2O_4)})]$

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Putting values in above equation, we get:

$\Delta H_{rxn}=[(2 mol\times 81.6 kJ/mol)+2 mol\times -241.8 kJ/mol)]-[(1 mol\times (50.6 kJ/mol))+(1 mol\times (9.16))]\\\\\Delta H_{rxn}=-380.16 kJ$

Hence, the enthalpy of the reaction is coming out to be -380.16 kJ.

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2 years ago

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Answer:

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