Use the Standard Reaction Enthalpies Given Below to Determine _DrH° $D _ { \mathrm { r } }$

question 30

Multiple Choice

Use the standard reaction enthalpies given below to determine _DrH° for the following reaction: P₄(g) + 10Cl₂(g) ? 4PCl₅(s)
_DrH°0= ?
Given:
PCl₅(s) ? PCl₃(g) + Cl₂(g) $D _ { \mathrm { r } }$ H°= +157 kJ
P₄(g) + 6Cl₂(g) ? 4PCl₃(g) $D _ { \mathrm { r } }$ H° = -1207 kJ

• A)-1835 kJ mol^-1
• B)-1364 kJ mol^-1
• C)-1050 kJ mol^-1
• D)-1786 kJ mol^-1
• E)-2100 kJ mol^-1

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Definitions:

Forecast Error

The difference between the actual outcome and the predicted value in a forecast, indicating the accuracy of forecasting methods.

Squares

Geometrical shapes with four equal sides and four right angles, or multiplications of a number by itself.

Mean Squared Error

A measure of the average squared differences between estimated and actual values, used to evaluate the accuracy of statistical models.

Exponential Smoothing

A time series forecasting method for univariate data that applies weighing factors which decrease exponentially over time.