At 25°C, the Standard Enthalpy of Formation of Anhydrous Sodium $\Delta$

question 107

Multiple Choice

At 25°C, the standard enthalpy of formation of anhydrous sodium carbonate is -1130.9 kJ/mol, whereas the standard enthalpy of formation of sodium carbonate monohydrate is -1430.1 kJ/mol.Determine $\Delta$ H° at 25°C for the reaction Na₂CO₃(s) + H₂O(l) $\rarr$ Na₂CO₃·H₂O(s) .
(Given: $\Delta$ H°_f[H₂O(l) ] = -285.8 kJ/mol)

• A)-585.0 kJ/mol
• B)-299.2 kJ/mol
• C)-285.8 kJ/mol
• D)-156.3 kJ/mol
• E)-13.4 kJ/mol

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Definitions:

Average Variable Costs

The total variable expenses of producing an item, divided by the quantity of items produced, accounting for costs that change with the production volume.

AVC Curve

The Average Variable Cost curve, in economics, represents how the variable cost per unit changes with the level of output.

AFC Curve

Average Fixed Costs curve; a graphical representation showing the average fixed costs of producing different levels of output, which typically decreases as output increases.

MC Curve

The marginal cost curve, which graphs the cost of producing one more unit of a good or service, showing how marginal cost varies with the quantity produced.