Octane (C₈H₁₈)undergoes Combustion According to the Following Thermochemical Equation: 2C₈H₁₈(l) $\rarr$

question 21

Multiple Choice

Octane (C₈H₁₈) undergoes combustion according to the following thermochemical equation: 2C₈H₁₈(l) + 25O₂(g) $\rarr$ 16CO₂(g) + 18H₂O(l)
$\Delta$ H°_rxn = -11,020 kJ/mol.
Given that $\Delta$ H°_f[CO₂(g) ] = -393.5 kJ/mol and $\Delta$ H°_f[H₂O(l) ] = -285.8 kJ/mol, calculate the standard enthalpy of formation of octane.

• A)-210 kJ/mol
• B)-11,230 kJ/mol
• C)22,040 kJ/mol
• D)-420 kJ/mol
• E)420 kJ/mol

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Definitions:

Eudicots

One of the two major groups of flowering plants, characterized by having two cotyledons (seed leaves), net-veined leaves, and flower parts usually in multiples of four or five.

Monocots

A group of flowering plants (angiosperms) that have a single embryonic leaf, or cotyledon, in their seeds.

Blade

The broad, flat part of a leaf or similar structure, specialized for photosynthesis in most plants.

Sessile

Describes organisms or parts thereof that are attached directly at the base and are not freely moving.