The Enthalpy of Vaporization of Tetrachloromethane, CCl₄, Is 30

question 20

Multiple Choice

The enthalpy of vaporization of tetrachloromethane, CCl₄, is 30.5 kJ mol^-1 at its normal boiling temperature of 350 K. Estimate the enthalpy of vaporization at 298 K, given that the molar constant pressure heat capacities of liquid and gaseous tetrachloromethane are 83.5 and 135 J K^-1 mol^-1.

• A) 27.8 kJ mol^-1
• B) 33.2 kJ mol^-1
• C) 30.5 kJ mol^-1
• D) 2.7 kJ mol^-1

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Definitions:

Fixed Costs

Costs that remain constant regardless of the amount of goods produced or sold in a brief timeframe, including charges like rent, salaries, and insurance.

Units of Production

A depreciation method that allocates the original cost of an asset over its total estimated production capacity.

Direct Materials Cost Variance

The difference between the actual cost of direct materials used in production and the standard cost of those materials.

Direct Materials Quantity Variance

The difference between the actual amount of direct materials used in production and the expected amount, based on standards, multiplied by the standard cost per unit.